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  • 1.
    Aakash, förnamn
    et al.
    Department of Electronics and Communication Engg., Birla Institute of Technology.
    Nordblad, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Mohan, Rajendra
    Department of Physics, National Institute of Technology Patna.
    Mukherjee, Samrat
    Department of Physics, National Institute of Technology Patna.
    Structural, magnetic and hyperfine characterizations of nanocrystalline Zn-Cd doped nickel ferrites2017In: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 441, p. 710-717Article in journal (Refereed)
    Abstract [en]

    In our present work, we have synthesized a series of Cd-Zn doped nickel ferrite ((Cd-0.5 Zn-x(x)) Ni0(.5)Fe(2)O(4); x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) through standard chemical co-precipitation method to study the influence of diamagnetic ions (Cd, Zn) on the magnetic properties of ferrites. XRD and Raman spectroscopy were employed for the structural characterizations. The refinement of the X-ray diffractogram data augmented by the Williamson-Hall plots showed the presence of Cd2+ vacancies and a strained crystal structure. The vibrational spectroscopy indicated the presence of lower space-group symmetry and a distorted crystal structure. Magnetic measurements showed the samples possessed low magnetic anisotropy along with a canted spin structure. The Mossbauer measurements confirmed the cation distribution and gave evidence of super transferred hyperfine interactions arising due to canted spin structure of the system.

  • 2.
    Abdi-Jalebi, Mojtaba
    et al.
    Univ Cambridge, Dept Phys, Cavendish Lab, JJ Thomson Ave, Cambridge, England.
    Pazoki, Meysam
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Philippe, Bertrand
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Dar, M. Ibrahim
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photon & Interfaces, Lausanne, Switzerland.
    Alsari, Mejd
    Univ Cambridge, Dept Phys, Cavendish Lab, JJ Thomson Ave, Cambridge, England.
    Sadhanala, Aditya
    Univ Cambridge, Dept Phys, Cavendish Lab, JJ Thomson Ave, Cambridge, England.
    Diyitini, Giorgio
    Univ Cambridge, Dept Mat Sci & Met, Charles Babbage Rd, Cambridge, England.
    Imani, Roghayeh
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Lilliu, Samuele
    Univ Sheffield, Dept Phys & Astron, Sheffield, S Yorkshire, England; UAE Ctr Crystallog, Dubai, U Arab Emirates.
    Kullgren, Jolla
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Rensmo, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Gratzel, Michael
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photon & Interfaces, Lausanne, Switzerland.
    Friend, Richard H.
    Univ Cambridge, Dept Phys, Cavendish Lab, JJ Thomson Ave, Cambridge, England.
    Dedoping of Lead Halide Perovskites Incorporating Monovalent Cations2018In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 12, no 7, p. 7301-7311Article in journal (Refereed)
    Abstract [en]

    We report significant improvements in the optoelectronic properties of lead halide perovskites with the addition of monovalent ions with ionic radii close to Pb2+. We investigate the chemical distribution and electronic structure of solution processed CH3NH3PbI3 perovskite structures containing Na+, Cu+, and Ag+, which are lower valence metal ions than Pb2+ but have similar ionic radii. Synchrotron X-ray diffraction reveals a pronounced shift in the main perovskite peaks for the monovalent cation-based films, suggesting incorporation of these cations into the perovskite lattice as well as a preferential crystal growth in Ag+ containing perovskite structures. Furthermore, the synchrotron X-ray photoelectron measurements show a significant change in the valence band position for Cu- and Ag-doped films, although the perovskite bandgap remains the same, indicating a shift in the Fermi level position toward the middle of the bandgap. Such a shift infers that incorporation of these monovalent cations dedope the n-type perovskite films when formed without added cations. This dedoping effect leads to cleaner bandgaps as reflected by the lower energetic disorder in the monovalent cation-doped perovskite thin films as compared to pristine films. We also find that in contrast to Ag+ and Cu+, Na+ locates mainly at the grain boundaries and surfaces. Our theoretical calculations confirm the observed shifts in X-ray diffraction peaks and Fermi level as well as absence of intrabandgap states upon energetically favorable doping of perovskite lattice by the monovalent cations. We also model a significant change in the local structure, chemical bonding of metal-halide, and the electronic structure in the doped perovskites. In summary, our work highlights the local chemistry and influence of monovalent cation dopants on crystallization and the electronic structure in the doped perovskite thin films.

  • 3.
    Abdu, Yassir
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Physics, Department of Physics and Materials Science, Physics III. Technology, Department of Engineering Sciences, Solid State Physics.
    Ericsson, Tore
    Department of Physics. Physics, Department of Physics and Materials Science, Physics III. Technology, Department of Engineering Sciences, Solid State Physics.
    Nordblad, Per
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Physics, Department of Physics and Materials Science, Physics III. Technology, Department of Engineering Sciences, Solid State Physics. Fasta tillståndets fysik.
    Field-induced local magnetic moments in γ (FCC) Fe-Ni anti –Invar alloys2004In: J. Mag. Mag. Mater, Vol. 280, p. 243-250Article in journal (Refereed)
  • 4. Ackeby, Susanne
    et al.
    Bollen, Math
    Munkhammar, Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Prosumer with demand-response: Distribution network impact and mitigation2013Report (Refereed)
  • 5.
    Ackeby, Susanne
    et al.
    STRI.
    Bollen, Math
    Luleå tekniska universitet.
    Munkhammar, Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Prosumer with demand-response:Distribution network impact and mitigation2013Report (Other academic)
    Abstract [en]

    This report is the result from a project funded by ELFORSK done by STRI. Theproject is studying the effects the introduction of so called “prosumers”(customers with own production) and electrical vehicles will have on differenttypes of networks. Four different cases are studied: covering urban and ruralareas with different types of customers.In the urban areas the power through the transformer will be the limitingfactor. The major impact in the cases studied is from the introduction ofproduction from photovoltaics at the customer-side of the meter. This willresult in an introduction of surplus due to production which in one case led toan increase of the absolute power through the transformer with more than30%, which resulted in transformer overloading.In the rural areas the voltage drop or rise will be the limiting factor. The casesstudied had already high voltage drops even in the base cases. In the casestudies it was seen that the voltage drop could be slightly reduced whenintroducing more local production, but the production also led to that voltagerise could appear. As a result the interval of the voltage variations wasincreased, which in turn leads to difficulties with designing the network suchthat neither overvoltage nor undervoltage occurs.Introducing control algorithms had a very positive effect on reducing the netproduction from the photovoltaics. Using both hard and soft curtailment madeit possible to remove all overcurrents or overvoltages. Using hard curtailment,where all production is turned off during overcurrent or overvoltage, leadshowever to a large reduction in energy from renewable energy sources.Therefore soft curtailment should as much as possible be used.The control algorithms studied for reducing the net consumption had a morelimited effect and even resulted in an increase of the maximum netconsumption. When trying to reduce the net consumption during an overload,the reason of the overload could only be moved in time and not removed as inthe case of reducing the net production. And since often the period duringwhich the power exceeds the limit is longer than the number of hours possibleto move the energy, sometimes moving the energy had an adverse effect.The model used for controlling the net consumption needs furtherdevelopment, but it is still possible to draw the conclusion that this type ofcontrol offers only limited possibilities for mitigating overload or undervoltage.The effects of introducing prosumers and more electrical vehicles as defined inthe selected cases did not show any alarming results in this study. However,studies to learn more about the possible consequences of changes atcustomer-side are important to be able to handle the impact of such changeson the network.Further future studies needed: database with load and production data;improved control algorithms; demonstration project; experience from othercountries and studies on reactive power compensation.

  • 6. Adell, M
    et al.
    Kanski, J
    Stanciu, V
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Solid State Physics. Fasta tillståndets fysik.
    Ilver, L
    Sadowski, J
    Svedlindh, P
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Solid State Physics. Fasta tillståndets fysik.
    Comment on “Mn interstitial diffusion in (Ga,Mn)As”2005In: Phys. Rev. Lett., Vol. 94, p. 139701-Article in journal (Refereed)
  • 7. Adell, M
    et al.
    Staniciu, V
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Solid State Physics. Fasta tillståndets fysik.
    Kanski, J
    Ilver, L
    Sadowski, J
    Domagala, J Z
    Svedlindh, P
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Solid State Physics. Fasta tillståndets fysik.
    Terki, F
    Hernandez, C
    Charar, S
    Post-growth annealing of (Ga,Mn)As under As capping – an alternative way to increase Tc2005In: Apåpl. Phys. Lett., Vol. 86, p. 112501-Article in journal (Refereed)
  • 8. Adell, Martin
    et al.
    Ilver, Lars
    Kanski, Janusz
    Stanciu, Victor
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Svedlindh, Peter
    Sadowski, Janusz
    Domagala, J.Z.
    Terki, F.
    Hernandez, C.
    Charar, S.
    Postgrowth annealing of (Ga,Mn)As under As capping: An alternative way to increase Tc2005In: Applied Physics Letters, Vol. 86, p. 112501-Article in journal (Refereed)
  • 9.
    Agthe, Michael
    et al.
    Stockholm Univ, Arrhenius Lab, Dept Mat & Environm Chem, SE-10691 Stockholm, Sweden..
    Wetterskog, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Bergström, Lennart
    Stockholm Univ, Arrhenius Lab, Dept Mat & Environm Chem, SE-10691 Stockholm, Sweden..
    Following the Assembly of Iron Oxide Nanocubes by Video Microscopy and Quartz Crystal Microbalance with Dissipation Monitoring2017In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, no 1, p. 303-310Article in journal (Refereed)
    Abstract [en]

    We have studied the growth of ordered arrays by evaporation-induced self-assembly of iron oxide nanocubes with edge lengths of 6.8 and 10.1 nm using video microscopy (VM) and quartz crystal microbalance with dissipation monitoring (QCM-D). Ex situ electron diffraction of the ordered arrays demonstrates that the crystal axes of the nanocubes are coaligned and confirms that the ordered arrays are mesocrystals. Time-resolved video microscopy shows that growth of the highly ordered arrays at slow solvent evaporation is controlled by particle diffusion and can be described by a simple growth model. The growth of each mesocrystal depends only on the number of nanoparticles within the accessible region irrespective of the relative time of formation. The mass of the dried mesocrystals estimated from the analysis of the bandwidth-shift-to-frequency-shift ratio correlates well with the total mass of the oleate-coated nanoparticles in the deposited dispersion drop.

  • 10.
    Ahlinder, Linnea
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Ekstrand-Hammarstrom, Barbro
    Geladi, Paul
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Large Uptake of Titania and Iron Oxide Nanoparticles in the Nucleus of Lung Epithelial Cells as Measured by Raman Imaging and Multivariate Classification2013In: Biophysical Journal, ISSN 0006-3495, E-ISSN 1542-0086, Vol. 105, no 2, p. 310-319Article in journal (Refereed)
    Abstract [en]

    It is a challenging task to characterize the biodistribution of nanoparticles in cells and tissue on a subcellular level. Conventional methods to study the interaction of nanoparticles with living cells rely on labeling techniques that either selectively stain the particles or selectively tag them with tracer molecules. In this work, Raman imaging, a label-free technique that requires no extensive sample preparation, was combined with multivariate classification to quantify the spatial distribution of oxide nanoparticles inside living lung epithelial cells (A549). Cells were exposed to TiO2 (titania) and/or alpha-FeO(OH) (goethite) nanoparticles at various incubation times (4 or 48 h). Using multivariate classification of hyperspectral Raman data with partial least-squares discriminant analysis, we show that a surprisingly large fraction of spectra, classified as belonging to the cell nucleus, show Raman bands associated with nanoparticles. Up to 40% of spectra from the cell nucleus show Raman bands associated with nanoparticles. Complementary transmission electron microscopy data for thin cell sections qualitatively support the conclusions.

  • 11.
    Ahlinder, Linnea
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Henych, Jiří
    Wiklund Lindström, Susanne
    Ekstrand-Hammarström, Barbro
    Stengl, Václav
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Graphene oxide nanoparticle attachment and its toxicity on living lung epithelial cells2015In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 5, no 73, p. 59447-59457Article in journal (Refereed)
    Abstract [en]

    Since its discovery, graphene and its oxidized form, graphene oxide (GO), have attracted interest in a wide range of technical applications. Concerns about their potential toxicity calls for scrutinized studies, but hitherto conflicting results have been reported which partly may be due to variations of synthesis and exposure procedures. Here we report on the attachment and toxicity of contamination-free graphene oxide nanoparticles (GONP) in living lung epithelial cells. The synthesis of chemically pure GONP was made by an improvement of the Hummer's method based on graphene exfoliated from graphite using high-intensity ultrasonication, resulting in two dimensional sheets with a lateral dimension in the range 200 nm to 3 mu m and thickness of 0.9 nm. Confocal Raman spectroscopy combined with multivariate analysis was used to study the interaction of GONP and living cells. It is shown that overlapping Raman bands due to GONPs and biomolecules in the cells can clearly be separated with this approach. Orthogonal partial least squares discriminant analysis was used to compare spectral data collected from cells exposed to GONP with spectral data collected from non-exposed control cells, and spectral data from cells exposed to a surfactant known to induce apoptosis. Our analyses show that GONP readily attach to the cells, forming sheets which cover a large fraction of the cell surfaces, and induce small chemical changes. In particular, chemical modifications of proteins and lipids in lung epithelial cells are inferred. GONPs do not, however, decrease cell viability. In contrast, enhanced cell proliferation is observed. Our results shed new light on the interactions of GO, and in contrast to some previous reports, suggest that GO is not toxic. The hyperspectral Raman spectroscopy analysis employed here should be applicable for other fields in nanomedicine as a label-free non-perturbing analytical method.

  • 12.
    Ahlinder, Linnea
    et al.
    Swedish Def Res Agcy, FOI, Cementvagen 20, SE-90182 Umea, Sweden..
    Lindstrom, Susanne Wiklund
    Swedish Def Res Agcy, FOI, Cementvagen 20, SE-90182 Umea, Sweden..
    Lejon, Christian
    Swedish Def Res Agcy, FOI, Cementvagen 20, SE-90182 Umea, Sweden..
    Geladi, Paul
    Swedish Univ Agr Sci, Dept Forest Biomat & Technol, SE-90183 Umea, Sweden..
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Noise Removal with Maintained Spatial Resolution in Raman Images of Cells Exposed to Submicron Polystyrene Particles2016In: NANOMATERIALS, ISSN 2079-4991, Vol. 6, no 5, article id UNSP 83Article in journal (Refereed)
    Abstract [en]

    The biodistribution of 300 nm polystyrene particles in A549 lung epithelial cells has been studied with confocal Raman spectroscopy. This is a label-free method in which particles and cells can be imaged without using dyes or fluorescent labels. The main drawback with Raman imaging is the comparatively low spatial resolution, which is aggravated in heterogeneous systems such as biological samples, which in addition often require long measurement times because of their weak Raman signal. Long measurement times may however induce laser-induced damage. In this study we use a super-resolution algorithm with Tikhonov regularization, intended to improve the image quality without demanding an increased number of collected pixels. Images of cells exposed to polystyrene particles have been acquired with two different step lengths, i.e., the distance between pixels, and compared to each other and to corresponding images treated with the super-resolution algorithm. It is shown that the resolution after application of super-resolution algorithms is not significantly improved compared to the theoretical limit for optical microscopy. However, to reduce noise and artefacts in the hyperspectral Raman images while maintaining the spatial resolution, we show that it is advantageous to use short mapping step lengths and super-resolution algorithms with appropriate regularization. The proposed methodology should be generally applicable for Raman imaging of biological samples and other photo-sensitive samples.

  • 13. Ahlinder, Linnea
    et al.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Hyperspektral analys av celler och vävnad exponerade för luftburna partiklar2010Report (Refereed)
  • 14.
    Ahlinder, Linnea
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Wiklund Lindström, Susanne
    Raman mapping and hyperspectral data analysis2010Report (Refereed)
  • 15.
    Ahlqvist, Carolina Marianne
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Projektorganiseringen som drivkraft och hinder för industriell förnyelse i byggindustrin: en fallstudie av Skandionkliniken2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Understanding how innovation and renewal occurs in an industry is important for how to manage technical development for individual companies. It is also important for creating a beneficial industrial context for renewal, from both a political and an industrial perspective, in which new solutions can arise and spread through the involvement of several actors of the industry. How innovation and renewal occurs in the construction industry in Sweden is however viewed differently. One challenge that has been pointed to is that most of the work performed in the construction industry is organized in projects, which in turn should affect how innovation and renewal can be achieved.

     

    The aim of this thesis is to provide an understanding of how the project organizing in the industry affects innovation and renewal. This is executed through a case study of the construction of Skandionkliniken, a proton therapy clinic, and by using an industrial network theory that challenges the traditional view of how innovation is achieved. One important understanding drawn from this study is that renewal is created in the interface between companies and their resources. The kinds of innovation and renewal that can take place in the projects highly rely on technical interdependencies and organizational features of the involved actors. Three conclusions are drawn from this study; firstly, innovation and renewal in the construction industry occurs gradually across projects, secondly, the type of innovation that occurs is not what is expected from a traditional point of view, and thirdly, therefore it is not necessarily obvious when or how it takes place, which has implications both for policy and company management.

  • 16. Ahniyaz, Anwar
    et al.
    Seisenbaeva, Gulam A.
    Häggström, Lennart
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Materials Science, Materials Physics.
    Kamali, Saeed
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Materials Science, Materials Physics.
    Kessler, Vadim G.
    Nordblad, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Johansson, Christer
    Bergström, Lennart
    Preparation of iron oxide nanocrystals by surfactant-free or oleic acid-assisted thermal decomposition of a Fe(III) alkoxide2008In: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 320, no 6, p. 781-787Article in journal (Refereed)
    Abstract [en]

    A new non-hydrolytic, alkoxide-based route was developed to synthesize iron oxide nanocrystals. Surfactant-free thermal decomposition of the iron 2-methoxy-ethoxide precursors results in the formation of uniform iron oxide nanocrystals with an average size of 5.6 nm. Transmission electron microscope study shows that the nanocrystals are protected against aggregation by a repulsive surface layer, probably originating from the alkoxy-alkoxide ligands. Addition of oleic acid resulted in monodisperse nanocrystals with an average size of 4 nm. Mössbauer analysis confirmed that the nanocrystals mainly consisted of maghemite. Analysis of the magnetic hysteresis loop measurements and the zero field and field cooled measurements displayed an excellent fit to established theories for single-domain superparamagnetic nanocrystals and the size of the magnetic domains correlated well to the crystallite size obtained from transmission electron microscope.

  • 17. Ahrentorp, Fredrik
    et al.
    Astalan, Andrea
    Blomgren, Jakob
    Jonasson, Christian
    Wetterskog, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Svedlindh, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Lak, Aidin
    Ludwig, Frank
    Van IJzendoorn, Leo J.
    Westphal, Fritz
    Gruettner, Cordula
    Gehrke, Nicole
    Gustafsson, Stefan
    Olsson, Eva
    Johansson, Christer
    Effective particle magnetic moment of multi-core particles2015In: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 380, p. 221-226Article in journal (Refereed)
    Abstract [en]

    In this study we investigate the magnetic behavior of magnetic multi-core particles and the differences in the magnetic properties of multi-core and single-core nanoparticles and correlate the results with the nanostructure of the different particles as determined from transmission electron microscopy (TEM). We also investigate how the effective particle magnetic moment is coupled to the individual moments of the single-domain nanocrystals by using different measurement techniques: DC magnetometry, AC susceptometry, dynamic light scattering and TEM. We have studied two magnetic multi-core particle systems BNF Starch from Micromod with a median particle diameter of 100 am and FeraSpin R from nanoPET with a median particle diameter of 70 nm - and one single-core particle system - SHP25 from Ocean NanoTech with a median particle core diameter of 25 nm. (C) 2014 Elsevier B.V. All rights reserved.

  • 18.
    Aijaz, Asim
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Ji, Yu-Xia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Granqvist, Claes G
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Niklasson, Gunnar A
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kubart, Tomás
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Low-temperature synthesis of thermochromic vanadium dioxide thin films using reactive magnetron sputtering2015In: Abstracts, 2015Conference paper (Refereed)
  • 19.
    Aijaz, Asim
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Ji, Yu-Xia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Montero, Jose
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Granqvist, Claes-Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kubart, Tomáš
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Deposition of thermochromic vanadium dioxide thin films by reactive high power impulse magnetron sputtering2014Conference paper (Other academic)
    Abstract [en]

    Vanadium dioxide exhibits a reversible phase transition from semiconducting state (monoclinic structure) to a metallic state (tetragonal structure) at ~68 oC. This so-called metal-insulator transition (MIT) entails thermochromic behavior manifested by large changes in optical properties, such as high infrared transmittance modulation in thin films, thereby making VO2-based films a suitable candidate for optical switching applications such as self-tunable infrared filters. Thermochromic VO2 thin films have been widely investigated for optical applications, but high growth temperatures (> 400 oC) required for synthesizing crystalline VO2 thin films, high MIT temperature (68 oC) as well as low visible transmittance (typically ~50%) limit their applicability for example for energy efficient smart windows.

     

    Synthesis of metal-oxide thin films using highly ionized vapor fluxes has been shown to facilitate low-temperature film growth as well as control over phase formation and resulting film properties. In the present work, we synthesize VO2 thin films by use of highly ionized vapor fluxes that are generated by high power impulse magnetron sputtering (HiPIMS). In order to establish a correlation between the plasma and film properties, we investigate the discharge characteristics by analyzing the discharge current-voltage characteristics under varied process parameters such as peak-power, pulse-width and gas phase composition and grow VO2 thin films under suitable process conditions. We investigate the effect of growth temperature (room temperature to 500 oC), energy of the deposition flux (controlled by substrate bias potential) and type of substrate (Si, glass, ITO-coated glass) on crystallinity, phase formation and on optical properties (visible transmittance and infrared modulation) of the resulting thin films. For reference, the discharge characteristics and properties of films deposited by pulsed direct current magnetron sputtering are also studied.         

  • 20.
    Aijaz, Asim
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Ji, Yu-Xia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Montero, Jose
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Niklasson, Gunnar A.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Granqvist, Claes G.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kubart, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Low-temperature synthesis of thermochromic vanadium dioxide thin films by reactive high power impulse magnetron sputtering2016In: Solar Energy Materials and Solar Cells, ISSN 0927-0248, E-ISSN 1879-3398, Vol. 149, p. 137-144Article in journal (Refereed)
    Abstract [en]

    Thermochromic (TC) vanadium dioxide thin films provide means for controlling solar energy throughput and can be used for energy-saving applications such as smart windows. One of the factors limiting the deployment of VO2 films in TC devices is the growth temperature tau(s). At present, temperatures in excess of 450 degrees C are required, which clearly can be an impediment especially for temperature-sensitive substrates. Here we address the issue of high tau(s) by synthesizing VO2 thin films from highly ionized fluxes of depositing species generated in high power impulse magnetron sputtering (HiPIMS) discharges. The use of ions facilitates low-temperature film growth because the energy of the depositing species can be readily manipulated by substrate bias. For comparison, films were also synthesized by pulsed direct current magnetron sputtering. Structural and optical characterization of VO2 thin films on ITO-coated glass substrates confirms previous results that HiPIMS allows tau(s) to be reduced from 500 to 300 degrees C. Importantly, we demonstrated that HiPIMS permits the composition and TC response of the films to be tuned by altering the energy of the deposition flux via substrate bias. An optimum ion energy of 100 eV was identified, which points at a potential for further reduction of tau(s) thereby opening new possibilities for industrially-relevant applications of VO2-based TC thin films. Weak TC activity was observed even at tau(s) approximate to 200 degrees C in HiPIMS-produced films.

  • 21.
    Ajamlou, Robin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Nyman, Emma
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Provisorisk takbelysning vid byggarbetsplatser: En studie av belysningens funktion och dess påverkan på yrkesarbetaren2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report explores the definitions of general- and work lighting in an indoor construction site and how the lighting affects a construction worker. This in order to clarify the controversial topic of: which purpose the ceiling lighting has, thus making the lighting plan optimal. This study was made in cooperation with Skanska Sweden AB. The main ceiling lighting-device in Skanska Sweden is a custom made LED-lamp which is the main tool that this research is based on. The main research methods are project site visits, interviews and surveys in combination with literature studies, and also practical measurements and simulations of the LED-lamps. The results of the interviews and surveys show that comprehension of the functions of the ceiling lighting varies among Skanska Sweden employees. While construction workers generally refer to work lighting when addressing ceiling lighting, the managers tend to refer to general lighting or as a tool to orientate the building. Although, how general lighting is defined, varies among the employees. With that said, the simulations reveal that a reasonable amount of a ceiling lighting will not fulfil the requirements for work lighting for all construction operations. Furthermore, our results from the interviews and surveys confirm those from previous studies; that lighting is essential for the well-being of people. A poorly illuminated workspace dulls one’s work performance and effects one’s health in both the short- and long terms. A well-lit workspace can, on the other hand, reduce the potential health and safety risks on a construction site and also ease multiple work tasks. There are currently no clear assembling routines of ceiling lighting. Therefore, to create consensus on the purpose of lighting and the health and safety prospects that come with it, this report recommends possible solutions and clarifications of the issues and misinterpretations in the matter.

  • 22.
    Akansel, Serkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Magnetization Dynamics in Ferromagnetic Thin Films: Evaluation of Different Contributions to Damping in Co2FeAl and FeCo Film Structures2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Static and dynamic magnetic properties of Co2FeAl and Fe65Co35 alloys have been investigated. Co2FeAl films were deposited at different temperatures and the deposition parameters were optimized with respect to structural and magnetic properties. As a result, a film with B2 crystalline phase was obtained without any post-annealing process. A lowest magnetic damping parameter of  was obtained for the film deposited at 573K. This obtained low value is comparable to the lowest values reported in research literature.  After optimizing the deposition parameters of this alloy, different seed layers and capping layers were added adjacent to the Co2FeAl layer and the effect of these layers on the magnetic relaxation was investigated. In addition to adding nonmagnetic layers to Co2FeAl, the dependence of the magnetic damping parameter with respect to the thickness of Co2FeAl was investigated by depositing films with different thicknesses. A temperature dependent study of the magnetic damping parameter was also performed and the measured damping parameters were compared with theoretically calculated intrinsic Gilbert damping parameters. Different extrinsic contributions to the magnetic damping, such as two magnon scattering, spin pumping, eddy-current damping and radiative damping, were identified and subtracted from the experimentally obtained damping parameter. Hence, it was possible to obtain the intrinsic damping parameter, that is called the Gilbert damping parameter.

    In the second part of the thesis, Fe65Co35 alloys were investigated in terms of static and dynamic magnetic properties. Fe65Co35 films were deposited without and with different seed layers in order to first understand the effect of the seed layer on static magnetic properties of the films, such as the coercivity of the films. Then the films with seed layers yielding the lowest coercivity were investigated in terms of dynamic magnetic properties. Fe65Co35 films with different rhenium dopant concentrations and with ruthenium as the seed and capping layer were also investigated. The purpose of this study was to increase the damping parameter of the films and an increase of about ~230% was obtained by adding the dopant to the structure. This study was performed at different temperatures and after subtraction of the extrinsic contributions to the damping, the experimental values were compared with theoretically calculated values of the Gilbert damping parameter. During the thesis work, magnetic looper and superconducting quantum interference device magnetometers set-ups were used for static magnetic measurements and cavity, broadband in-plane and broadband out-of-plane ferromagnetic resonance set-ups were used for dynamic measurements.

    List of papers
    1. Thickness dependent enhancement of damping in Co2FeAl/β-Ta thin films
    Open this publication in new window or tab >>Thickness dependent enhancement of damping in Co2FeAl/β-Ta thin films
    Show others...
    2018 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 97, no 13, article id 134421Article in journal (Refereed) Published
    Abstract [en]

    In the present work Co2FeAl (CFA) thin films were deposited by ion beam sputtering on Si (100) substrates at the optimized deposition temperature of 300°C. A series of CFA films with different thickness (tCFA ); 8, 10, 12, 14, 16, 18 and 20 nm were prepared and all samples were capped with a 5 nm thick b-Ta layer. The thickness dependent static and dynamic properties of the films were studied by SQUID magnetometry, in-plane as well as out-of-plane broadband VNA-FMR measurements and angle dependent cavity FMR measurements. The saturation magnetization and the coercive field were found to be weakly thickness dependent and lie in the range 900 – 950 kA/m and 0.53 – 0.87 kA/m, respectively. The effective damping parameter ( αeff) extracted from in-plane and out-of-plane FMR results reveal a 1/tCFA dependence, the values for the in-plane αeff being larger due to two-magnon scattering (TMS). The origin of the αeff thickness dependence is spin pumping into the non-magnetic b-Ta layer and in case of the in-plane  αeff also a thickness dependent TMS contribution. From the out-of-plane FMR results, it was possible to disentangle the different contributions to αeff   and to the extract values for the intrinsic Gilbert damping (αG ) and the effective spin-mixing conductance (g_eff^↑↓ ) of the CFA/ b-Ta interface, yielding αG=1.1X10-3 and g_eff^↑↓=2.90x1019 m-2.

    Place, publisher, year, edition, pages
    American Physical Society, 2018
    Keywords
    Magnetization dynamics, magnetic thin films, Gilbert damping, ferromagnetic resonance
    National Category
    Condensed Matter Physics Materials Engineering
    Research subject
    Physics with spec. in Atomic, Molecular and Condensed Matter Physics
    Identifiers
    urn:nbn:se:uu:diva-345848 (URN)10.1103/PhysRevB.97.134421 (DOI)000430544300002 ()
    Funder
    Knut and Alice Wallenberg Foundation, 2012.0031
    Available from: 2018-03-12 Created: 2018-03-12 Last updated: 2018-06-26Bibliographically approved
    2. Enhanched Gilbert Damping in Re doped FeCo Films: A combined experimental and theoretical study
    Open this publication in new window or tab >>Enhanched Gilbert Damping in Re doped FeCo Films: A combined experimental and theoretical study
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The effects of rhenium doping in the range 0 – 10 at% on the static and dynamic magnetic properties of Fe65Co35 thin films have been studied experimentally as well as with first principles electronic structure calculations focussing on the change of the saturation magnetization (Ms ) and the Gilbert damping parameter (α ). Both experimental and theoretical results show that Ms decreases with increasing Re doping level, while at the same time α increases.  The experimental low temperature saturation magnetic induction exhibits a 29% decrease, from 2.31T to 1.64T, in the investigated doping concentration range, which is more than predicted by the theoretical calculations. The room temperature value of the damping parameter obtained from ferromagnetic resonance measurements, correcting for extrinsic contributions to the damping, is for the undoped sample 2.7X103, which is close to the Gilbert damping parameter extracted from the theoretical calculations. The room temperature experimental value for the damping parameter increases to  9X103 when doping with 10 at% Re; the corresponding increase of the Gilbert damping parameter obtained from theoretical calculations is 7.3X103. Both experimental and theoretical values for the damping parameter weakly decrease with decreasing temperature.

    Keywords
    Magnetization dynamics, magnetic thin films, Gilbert damping, ferromagnetic resonance
    National Category
    Condensed Matter Physics
    Research subject
    Physics with spec. in Atomic, Molecular and Condensed Matter Physics
    Identifiers
    urn:nbn:se:uu:diva-345854 (URN)
    Funder
    Knut and Alice Wallenberg Foundation, 2012.0031
    Available from: 2018-03-12 Created: 2018-03-12 Last updated: 2018-03-12
    3. Effect of seed layers on dynamic and static magnetic properties of Fe65Co35 thin films
    Open this publication in new window or tab >>Effect of seed layers on dynamic and static magnetic properties of Fe65Co35 thin films
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    2018 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 51, no 30, article id 305001Article in journal (Refereed) Published
    Abstract [en]

    Fe65Co35 thin films have been deposited on SiO2 substrates using sputtering technique with different choices of seed layer; Ru, Ni82.5Fe17.5, Rh, Y and Zr. Best soft magnetic properties were observed with seed layers of Ru, Ni82.5Fe17.5 and Rh. Adding these seed layers, the coercivity of the Fe65Co35 films decreased to values of around 1.5 mT, which can be compared to the value of 12.5 mT obtained for films deposited without seed layer. Further investigations were performed on samples with these three seed layers in terms of dynamic magnetic properties, both on as prepared and annealed samples, using constant frequency cavity and broadband ferromagnetic resonance measurements. Damping parameters of around 8.0X10-3 and 4.5X10-3 were obtained from in-plane and out-of-plane measurements, respectively, for as prepared samples, values that were reduced to 6.5X10-3 and 4.0X10-3 for annealed samples.

    Keywords
    Magnetization dynamics, magnetic thin films, Gilbert damping, ferromagnetic resonance
    National Category
    Condensed Matter Physics Engineering and Technology
    Research subject
    Physics with spec. in Atomic, Molecular and Condensed Matter Physics
    Identifiers
    urn:nbn:se:uu:diva-345853 (URN)10.1088/1361-6463/aaccc0 (DOI)000437408700001 ()
    Funder
    Knut and Alice Wallenberg Foundation, 2012.0031
    Available from: 2018-03-12 Created: 2018-03-12 Last updated: 2018-10-12Bibliographically approved
    4. Growth of Co2FeAl Heusler alloy thin films on Si(100) having very small Gilbert damping by Ion beam sputtering
    Open this publication in new window or tab >>Growth of Co2FeAl Heusler alloy thin films on Si(100) having very small Gilbert damping by Ion beam sputtering
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    2016 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 28692Article in journal (Refereed) Published
    Abstract [en]

    The influence of growth temperature T-s (300-773 K) on the structural phase ordering, static and dynamic magnetization behaviour has been investigated in ion beam sputtered full Heusler alloy Co2FeAl (CFA) thin films on industrially important Si(100) substrate. The B2 type magnetic ordering is established in these films based on the clear observation of the (200) diffraction peak. These ion beam sputtered CFA films possess very small surface roughness of the order of subatomic dimensions (<3 angstrom) as determined from the fitting of XRR spectra and also by AFM imaging. This is supported by the occurrence of distinct Kiessig fringes spanning over the whole scanning range (similar to 4 degrees) in the x-ray reflectivity (XRR) spectra. The Gilbert damping constant alpha and effective magnetization 4 pi M-eff are found to vary from 0.0053 +/- 0.0002 to 0.0015 +/- 0.0001 and 13.45 +/- 00.03 kG to 14.03 +/- 0.04 kG, respectively. These Co2FeAl films possess saturation magnetization ranging from 4.82 +/- 0.09 to 5.22 +/- 0.10 mu(B)/f.u. consistent with the bulk L2(1)-type ordering. A record low alpha-value of 0.0015 is obtained for Co2FeAl films deposited on Si substrate at T-s similar to 573 K.

    National Category
    Other Physics Topics Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-299867 (URN)10.1038/srep28692 (DOI)000378783900001 ()27357004 (PubMedID)
    Available from: 2016-07-28 Created: 2016-07-28 Last updated: 2018-03-12Bibliographically approved
    5. Static and dynamic properties of Co2FeAl thin films: Effect of MgO and Ta as capping layers
    Open this publication in new window or tab >>Static and dynamic properties of Co2FeAl thin films: Effect of MgO and Ta as capping layers
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    2017 (English)In: 61ST DAE-SOLID STATE PHYSICS SYMPOSIUM, 2017, Vol. 1832, article id 080007-1Conference paper, Published paper (Refereed)
    Abstract [en]

    The influence of MgO and Ta capping layers on the static and dynamic magnetic properties of Co2FeAl (CFA) Heusler alloy thin films has been investigated. It is observed that the CFA film deposited with MgO capping layer is preeminent compared to the uncapped or Ta capped CFA film. In particular, the magnetic inhomogeneity contribution to the ferromagnetic resonance line broadening and damping constant are found to be minimal for the MgO capped CFA thin film i.e., 0.12±0.01 Oe and 0.0074±0.00014, respectively. The saturationmagnetization was found to be 960±25emu/cc.

    Series
    AIP Conference Proceedings, ISSN 0094-243X
    Keywords
    Heusler alloy, MgO, Gilbert damping
    National Category
    Physical Sciences Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-332482 (URN)10.1063/1.4980467 (DOI)000412824400289 ()978-0-7354-1500-3 (ISBN)
    Conference
    61st DAE-Solid State Physics Symposium, DEC 26-30, 2016, KIIT Univ, Bhubaneswar, INDIA
    Projects
    Knut and Alice Wallenberg (KAW) Foundation, Grant No. KAW 2012.0031.
    Available from: 2017-10-27 Created: 2017-10-27 Last updated: 2018-03-29Bibliographically approved
    6. Temperature-dependent Gilbert damping of Co2FeAl thin films with different degree of atomic order
    Open this publication in new window or tab >>Temperature-dependent Gilbert damping of Co2FeAl thin films with different degree of atomic order
    Show others...
    2017 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 96, no 224425Article in journal (Refereed) Published
    Abstract [en]

    Half-metallicity and low magnetic damping are perpetually sought for spintronics materials, and full Heusler compounds in this respect provide outstanding properties. However, it is challenging to obtain the well-ordered half-metallic phase in as-deposited full Heusler compound thin films, and theory has struggled to establish a fundamental understanding of the temperature-dependent Gilbert damping in these systems. Here we present a study of the temperature-dependent Gilbert damping of differently ordered as-deposited Co2FeAl full Heusler compound thin films. The sum of inter- and intraband electron scattering in conjunction with the finite electron lifetime in Bloch states governs the Gilbert damping for the well-ordered phase, in contrast to the damping of partially ordered and disordered phases which is governed by interband electronic scattering alone. These results, especially the ultralow room-temperature intrinsic damping observed for the well-ordered phase, provide fundamental insights into the physical origin of the Gilbert damping in full Heusler compound thin films.

    Place, publisher, year, edition, pages
    American Physical Society, 2017
    Keywords
    Gilbert damping, full Heusler compound, Temperature Dependent Gilbert damping, Thin Films, Density of states
    National Category
    Condensed Matter Physics Engineering and Technology
    Research subject
    Engineering Science with specialization in Solid State Physics
    Identifiers
    urn:nbn:se:uu:diva-337305 (URN)10.1103/PhysRevB.96.224425 (DOI)000418572700007 ()
    Funder
    Knut and Alice Wallenberg Foundation, KAW 2012.0031Göran Gustafsson Foundation for promotion of scientific research at Uppala University and Royal Institute of Technology, GGS1403ASwedish National Infrastructure for Computing (SNIC)
    Available from: 2017-12-22 Created: 2017-12-22 Last updated: 2018-03-12
  • 23.
    Akansel, Serkan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kumar, Ankit
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Behera, Nilamani
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Husain, Sajid
    Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016, India.
    Brucas, Rimantas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Chaudhary, Sujeet
    Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016, India.
    Svedlindh, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Thickness dependent enhancement of damping in Co2FeAl/β-Ta thin films2018In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 97, no 13, article id 134421Article in journal (Refereed)
    Abstract [en]

    In the present work Co2FeAl (CFA) thin films were deposited by ion beam sputtering on Si (100) substrates at the optimized deposition temperature of 300°C. A series of CFA films with different thickness (tCFA ); 8, 10, 12, 14, 16, 18 and 20 nm were prepared and all samples were capped with a 5 nm thick b-Ta layer. The thickness dependent static and dynamic properties of the films were studied by SQUID magnetometry, in-plane as well as out-of-plane broadband VNA-FMR measurements and angle dependent cavity FMR measurements. The saturation magnetization and the coercive field were found to be weakly thickness dependent and lie in the range 900 – 950 kA/m and 0.53 – 0.87 kA/m, respectively. The effective damping parameter ( αeff) extracted from in-plane and out-of-plane FMR results reveal a 1/tCFA dependence, the values for the in-plane αeff being larger due to two-magnon scattering (TMS). The origin of the αeff thickness dependence is spin pumping into the non-magnetic b-Ta layer and in case of the in-plane  αeff also a thickness dependent TMS contribution. From the out-of-plane FMR results, it was possible to disentangle the different contributions to αeff   and to the extract values for the intrinsic Gilbert damping (αG ) and the effective spin-mixing conductance (g_eff^↑↓ ) of the CFA/ b-Ta interface, yielding αG=1.1X10-3 and g_eff^↑↓=2.90x1019 m-2.

  • 24.
    Akansel, Serkan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kumar, Ankit
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Venugopal, Vijayaharan A.
    Seagate Technol, Londonderry BT48 0BF, North Ireland.
    Esteban-Puyuelo, Raquel
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Banerjee, Rudra
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Autieri, Carmine
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Brucas, Rimantas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Behera, Nilamani
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Sortica, Mauricio A.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Primetzhofer, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Basu, Swaraj
    Seagate Technol, Londonderry BT48 0BF, North Ireland.
    Gubbins, Mark A.
    Seagate Technol, Londonderry BT48 0BF, North Ireland.
    Sanyal, Biplab
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Svedlindh, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Enhanced Gilbert damping in Re-doped FeCo films: Combined experimental and theoretical study2019In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 99, no 17, article id 174408Article in journal (Refereed)
    Abstract [en]

    The effects of rhenium doping in the range 0-10 at.% on the static and dynamic magnetic properties of Fe65Co35 thin films have been studied experimentally as well as with first-principles electronic structure calculations focusing on the change of the saturation magnetization (M-s) and the Gilbert damping parameter (alpha). Both experimental and theoretical results show that M-s decreases with increasing Re-doping level, while at the same time alpha increases. The experimental low temperature saturation magnetic induction exhibits a 29% decrease, from 2.31 to 1.64 T, in the investigated doping concentration range, which is more than predicted by the theoretical calculations. The room temperature value of the damping parameter obtained from ferromagnetic resonance measurements, correcting for extrinsic contributions to the damping, is for the undoped sample 2.1 x 10(-3), which is close to the theoretically calculated Gilbert damping parameter. With 10 at.% Re doping, the damping parameter increases to 7.8 x 10(-3), which is in good agreement with the theoretical value of 7.3 x 10(-3). The increase in damping parameter with Re doping is explained by the increase in the density of states at the Fermi level, mostly contributed by the spin-up channel of Re. Moreover, both experimental and theoretical values for the damping parameter weakly decrease with decreasing temperature.

  • 25.
    Akansel, Serkan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kumar, Ankit
    Venugopal, Vijayaharan
    Banerjee, Rudra
    Autieri, Carmine
    Brucas, Rimantas
    Behera, Nilamani
    Sortica, Mauricio
    Primetzhofer, Daniel
    Basu, Swaraj
    Gubbins, Mark
    Sanyal, Biplab
    Svedlindh, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Enhanched Gilbert Damping in Re doped FeCo Films: A combined experimental and theoretical studyManuscript (preprint) (Other academic)
    Abstract [en]

    The effects of rhenium doping in the range 0 – 10 at% on the static and dynamic magnetic properties of Fe65Co35 thin films have been studied experimentally as well as with first principles electronic structure calculations focussing on the change of the saturation magnetization (Ms ) and the Gilbert damping parameter (α ). Both experimental and theoretical results show that Ms decreases with increasing Re doping level, while at the same time α increases.  The experimental low temperature saturation magnetic induction exhibits a 29% decrease, from 2.31T to 1.64T, in the investigated doping concentration range, which is more than predicted by the theoretical calculations. The room temperature value of the damping parameter obtained from ferromagnetic resonance measurements, correcting for extrinsic contributions to the damping, is for the undoped sample 2.7X103, which is close to the Gilbert damping parameter extracted from the theoretical calculations. The room temperature experimental value for the damping parameter increases to  9X103 when doping with 10 at% Re; the corresponding increase of the Gilbert damping parameter obtained from theoretical calculations is 7.3X103. Both experimental and theoretical values for the damping parameter weakly decrease with decreasing temperature.

  • 26.
    Akansel, Serkan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Venugopal, Vijayaharan
    Kumar, Ankit
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Gupta, Rahul
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Brucas, Rimantas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    George, Sebastian
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Neagu, Alexandra
    Tai, Cheuk-Wai
    Gubbins, Mark
    Andersson, Gabriella
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Svedlindh, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Effect of seed layers on dynamic and static magnetic properties of Fe65Co35 thin films2018In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 51, no 30, article id 305001Article in journal (Refereed)
    Abstract [en]

    Fe65Co35 thin films have been deposited on SiO2 substrates using sputtering technique with different choices of seed layer; Ru, Ni82.5Fe17.5, Rh, Y and Zr. Best soft magnetic properties were observed with seed layers of Ru, Ni82.5Fe17.5 and Rh. Adding these seed layers, the coercivity of the Fe65Co35 films decreased to values of around 1.5 mT, which can be compared to the value of 12.5 mT obtained for films deposited without seed layer. Further investigations were performed on samples with these three seed layers in terms of dynamic magnetic properties, both on as prepared and annealed samples, using constant frequency cavity and broadband ferromagnetic resonance measurements. Damping parameters of around 8.0X10-3 and 4.5X10-3 were obtained from in-plane and out-of-plane measurements, respectively, for as prepared samples, values that were reduced to 6.5X10-3 and 4.0X10-3 for annealed samples.

  • 27.
    Akhtar, Sultan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Experimental Physics.
    Strömberg, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Zardán Gómez de la Torre, Teresa
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Russell, Camilla
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
    Gunnarsson, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Nilsson, Mats
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
    Svedlindh, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Leifer, Klaus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Experimental Physics.
    Real-Space Transmission Electron Microscopy Investigations of Attachment of Functionalized Magnetic Nanoparticles to DNA-Coils Acting as a Biosensor2010In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 114, no 41, p. 13255-13262Article in journal (Refereed)
    Abstract [en]

    The present work provides the first real-space analysis of nanobead-DNA coil interactions. Immobilization of oligonucleotide-functionalized magnetic nanobeads in rolling circle amplified DNA-coils was studied by complex magnetization measurements and transmission electron microscopy (TEM), and a statistical analysis of the number of beads hybridized to the DNA-coils was performed. The average number of beads per DNAcoil using the results from both methods was found to be around 6 and slightly above 2 for samples with 40 and 130 nm beads, respectively. The TEM analysis supported an earlier hypothesis that 40 nm beads are preferably immobilized in the interior of DNA-coils whereas 130 nm beads, to a larger extent, are immobilized closer to the exterior of the coils. The methodology demonstrated in the present work should open up new possibilities for characterization of interactions of a large variety of functionalized nanoparticles with macromolecules, useful for gaining more fundamental understanding of such interactions as well as for optimizing a number of biosensor applications.

  • 28.
    Akhter, Shahida
    et al.
    Univ Chittagong, Dept Phys, Chittagong 4331, Bangladesh..
    Hakim, M. A.
    BUET, Dept Glass & Ceram Engn, Dhaka, Bangladesh..
    Hoque, S. M.
    Atom Energy Ctr, Mat Sci Div, Dhaka 1000, Bangladesh..
    Mathieu, Roland
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Nordblad, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Glassy behavior of diluted Cu-Zn ferrites2018In: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 452, p. 261-265Article in journal (Refereed)
    Abstract [en]

    The magnetic behavior of Zn substituted Cu-Zn spinel ferrites having chemical formula Cu1-xZnxFe2O4 (x = 0.7, 0.8, 0.9 and 1.0) has been studied by SQUID magnetometry, by means of magnetic hysteresis, field-cooled (FC) and zero-field-cooled (ZFC) magnetization, memory effect and low field ac susceptibility measurements. These measurements suggest that the ferrimagnetic phase of the x <= 0.8 samples is gradually turned into a spin glass (x >= 0.9). The compound with x = 0.9 exhibits the typical dynamical behavior of spin glasses, with indication of aging, rejuvenation and memory effects. The evolution of the magnetic properties of Cu-Zn spinel ferrites with substitution of Zn for Cu is discussed.

  • 29. Akhter, Shahida
    et al.
    Paul, D. P.
    Hoque, S. M.
    Hakim, M. A.
    Hudl, Matthias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Mathieu, Roland
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Nordblad, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Magnetic and magnetocaloric properties of Cu1-xZnxFe2O4 (x=0.6, 0.7, 0.8) ferrites2014In: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 367, p. 75-80Article in journal (Refereed)
    Abstract [en]

    The effect of Zn substitution on the magnetic and magnetocaloric properties of Cu1-xZnxFe2O4 (x=0.6, 0.7, 0.8) ferrites over a wide temperature range has been investigated. The polycrystalline samples were synthesized using the solid-state reaction at sintering temperature 1050 degrees C (1323 K) for 2 h and has been characterized by SQUID magnetometry. Magnetization versus temperature showed that all samples exhibit a paramagnetic to ferromagnetic transition with decreasing temperature. The Curie temperature T-c is found to decrease from 373 K for x=0.6 to 140 K for x=0.8 as well as the saturation magnetization Ms which shifts from 100 to 44 emu/gm. The magnetocaloric effect was obtained by measuring a family of M-I1 curves at set temperature intervals and calculating the entropy change, LIS for this system using the Maxwell relation. The AS of all samples increased with increasing applied field and showed a maximum around their respective 'Fe. The entropy change (Delta S) decreased with increasing Zn content, whereas the relative cooling power (RCP) slightly increased. The large RCP and Delta S found in Zn substitution Cu-Zn ferrites will be interesting for magnetic refrigeration near room temperature.

  • 30.
    Alarcón, Mathias
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Landau, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Resilience-enhancement through Renewable Energy Microgrid Systems in rural El Salvador2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This Master thesis investigates how Renewable Energy Microgrid Systems (REMS) can enhance resilience for a rural grid-connected community in El Salvador. The study examines the optimally resilient design of a grid-connected PV-Wind-Battery hybrid energy system. The optimally resilient system configuration was determined based on energy affordability, defined as minimum net present cost (NPC) and energy reliability, which was defined as a 1% maximum annual capacity shortage. The system modelling and optimisation was performed in the HOMER (Hybrid Optimisation of Multiple Energy Resources) software, where the system was optimised for different scenarios.

    The results of this study show that REMS can enhance resilience by lowering electricity costs for the community and thus increasing energy affordability. However, the REMS did not manage to make an equally substantial impact on energy reliability, due to the grid performance that proved to be high with few annual power outages. Besides the grid connection, the optimally resilient system was driven entirely by PV energy since it proved to be highly profitable. Wind power and battery storage were excluded from the optimally resilient system since they did not contribute to affordability and the capacity shortage limit was met already from the PV unit and the grid. Furthermore, the results show that self-sufficiency can be provided with REMS from the local energy resources, but that it is unrealistic with current costs due to the high battery prices. The study concludes that REMS should be considered as a legitimate resilience measure in rural El Salvador.

  • 31.
    Alenius, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Analys och vidareutveckling av marknadsstyrd effekttariff inom eldistribution: En fallstudie av Sandviken Energi Elnät AB:s effekttariff2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis evaluates the incentives of a newly implemented market controlled network tariff by analyzing consumption data and constructing a time-differentiated debiting model. The tariff was implemented by Sandviken Energi Elnät AB and the thesis evaluates its customers consumption data compared to data provided by Sundsvall Elnät AB. The differences in data is evaluated by statistical tests of Students t-test, Bayesian t-test and χ2-test with the result that no statistically significant change in user pattern can be found and thus an elucidation of the incentives must be made in the form of a hourly time-differentiated debating model. The thesis also evaluates the cost incentives of the model compared to spot prices where it is shown that the tariff model can benefit much from the spot prices hourly incentives in its hourly time-differentiated model. Five time-differentiated models were constructed and presented where three uses a color coding scheme. The conclusion is that a color coded time-differentiated tariff should give the costumers clear and cost-effective incentives.

  • 32.
    Ali, Hasan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Eriksson, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, FREIA. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Li, Hu
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Jafri, S. Hassan M.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kumar, M. S. Sharath
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Ögren, Jim
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Ziemann, Volker
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Leifer, Klaus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    An electron energy loss spectrometer based streak camera for time resolved TEM measurements2017In: Ultramicroscopy, ISSN 0304-3991, E-ISSN 1879-2723, Vol. 176, p. 5-10Article in journal (Refereed)
    Abstract [en]

    We propose an experimental setup based on a streak camera approach inside an energy filter to measure time resolved properties of materials in the transmission electron microscope (TEM). In order to put in place the streak camera, a beam sweeper was built inside an energy filter. After exciting the TEM sample, the beam is swept across the CCD camera of the filter. We describe different parts of the setup at the example of a magnetic measurement. This setup is capable to acquire time resolved diffraction patterns, electron energy loss spectra (EELS) and images with total streaking times in the range between 100 ns and 10 μs.

  • 33.
    Alm, Oscar
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Inorganic Chemistry. Technology, Department of Engineering Sciences, Solid State Physics. oorganisk kemi.
    Landström, Lars
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Inorganic Chemistry. Technology, Department of Engineering Sciences, Solid State Physics. oorganisk kemi.
    Boman, Mats
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Inorganic Chemistry. Technology, Department of Engineering Sciences, Solid State Physics. oorganisk kemi.
    Granqvist, Claes-Göran
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Inorganic Chemistry. Technology, Department of Engineering Sciences, Solid State Physics. Fasta tillståndets fysik.
    Heszler, Peter
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Inorganic Chemistry. Technology, Department of Engineering Sciences, Solid State Physics. Fasta tillståndets fysik.
    Tungsten oxide nanoparticles synthesised by laser assisted homogeneous gas-phase nucleation2005In: Applied Surface Science, Vol. 247, no 1-4, p. 262-267Article in journal (Refereed)
    Abstract [en]

    Tungsten oxide nanoparticles were generated by excimer (ArF) laser assisted chemical vapor deposition from WF6/H2/O2/Ar gas mixtures. The deposited particles were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy. The deposition rate as a function of the partial pressures of the reactants and of the laser fluence was measured by X-ray fluorescence spectroscopy. The mean diameter of the deposited tungsten oxide particles varied with the experimental parameters and was typically 23 nm. Particles with a higher degree of crystallinity were observed at a laser fluence exceeding 130 mJ/cm2, and X-ray amorphous particles were obtained below 110 mJ/cm2. The amorphous tungsten oxide had a stoichiometry ranging from WO2.7 to WO3. Deposits were formed only when hydrogen was present in the gas mixture.

  • 34.
    Almqvist, Bjarne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Björk, Andreas
    Mattsson, Hannes B.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Hedlund, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Gunnarsson, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Malehmir, Alireza
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Högdahl, Karin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Bäckström, Emma
    Marsden, Paul
    Magnetic characterisation of magnetite and hematite from the Blötberget apatite-iron-oxide deposits (Bergslagen), south-central Sweden2019In: Canadian journal of earth sciences (Print), ISSN 0008-4077, E-ISSN 1480-3313Article in journal (Refereed)
    Abstract [en]

    Rock magnetic measurements were carried out on drill core material and hand specimens from the Blötberget apatite-iron oxide deposit in the Bergslagen ore province, south-central Sweden, to characterise their magnetic properties. Measurements included several kinds of magnetic susceptibility and hysteresis parameters. Petrographic and scanning electron microscopy (SEM) were used to independently identify and quantify the amount and type of magnetite and hematite. Two hematite-rich samples were studied with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to quantify the trace element chemistry in hematite and investigate the potential influence of trace elements on magnetic properties. Three aspects of this study are noteworthy. 1) Hematite-rich samples display strong anisotropy of magnetic susceptibility, which is likely to affect the appearance and modelling of magnetic anomalies. 2) The magnitude-drop in susceptibility across Curie and Néel temperature transitions show significant correlation with the respective weight percent (wt%) of magnetite and hematite. Temperature dependent magnetic susceptibility measurements can therefore be used to infer the amounts of both magnetite and hematite. 3) observations of a strongly depressed Morin transition at ca -60 to -70 C (200 to 210 K) are made during low-temperature susceptibility measurements. This anomalous Morin transition is most likely related to trace amounts of V and Ti that substitute for Fe in the hematite. When taken together, these magnetic observations improve the understanding of the magnetic anomaly signature of the Blötberget apatite-iron oxide deposits and may potentially be utilised in a broader context when assessing similar (Paleoproterozoic) apatite-iron oxide systems.

  • 35.
    Ammon, Anton
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Comparing the benefits of energy saving measures with seasonal solar thermal heat storage2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]