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Klintenberg, MattiasORCID iD iconorcid.org/0000-0001-6437-5889
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Publications (10 of 40) Show all publications
Metsanurk, E. & Klintenberg, M. (2019). Sampling-dependent systematic errors in effective harmonic models. Physical Review B, 99(18), Article ID 184304.
Open this publication in new window or tab >>Sampling-dependent systematic errors in effective harmonic models
2019 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 99, no 18, article id 184304Article in journal (Refereed) Published
Abstract [en]

Effective harmonic methods allow for calculating temperature-dependent phonon frequencies by incorporating the anharmonic contributions into an effective harmonic Hamiltonian. The systematic errors arising from such an approximation are explained theoretically and quantified by density-functional-theory-based numerical simulations. Two techniques with different approaches for sampling the finite-temperature phase space in order to generate the force-displacement data are compared. It is shown that the error in free energy obtained by using either can exceed that obtained from 0 K harmonic lattice dynamics analysis, which neglects the anharmonic effects.

Place, publisher, year, edition, pages
AMER PHYSICAL SOC, 2019
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-386450 (URN)10.1103/PhysRevB.99.184304 (DOI)000469325500005 ()
Available from: 2019-06-24 Created: 2019-06-24 Last updated: 2019-06-24Bibliographically approved
Butorin, S., Kvashnina, K. O., Klintenberg, M., Kavcic, M., Zitnik, M., Bucar, K., . . . Lenoir, B. (2018). Effect of Ag Doping on Electronic Structure of Cluster Compounds AgxMo9Se11 (x = 3.4, 3.9). ACS APPLIED ENERGY MATERIALS, 1(8), 4032-4039
Open this publication in new window or tab >>Effect of Ag Doping on Electronic Structure of Cluster Compounds AgxMo9Se11 (x = 3.4, 3.9)
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2018 (English)In: ACS APPLIED ENERGY MATERIALS, ISSN 2574-0962, Vol. 1, no 8, p. 4032-4039Article in journal (Refereed) Published
Abstract [en]

The electronic structure of AgxMo9Se11 as a potential material for thermoelectric applications was studied using high-energy-resolution fluorescence-detection X-ray absorption spectroscopy (HERFD-XAS) and the resonant inelastic X-ray scattering (RIXS) technique. The experiments were supported by first-principle calculations using density functional theory (DFT). The analysis of obtained spectra indicate the presence of subvalent (less than 1+) Ag in AgxMo9Se11. The advanced HERFD-XAS measurements allowed us to resolve the contribution of the electronic states at the Fermi level of AgxMo9Se11 and to monitor its dependence on the x value. A comparison of the experimental data with the results of the DFT calculations suggests the importance of the Ag2-type sites with the shortest Ag–Se distance for affecting the properties of AgxMo9Se11.

Keywords
thermoelectric applications, X-ray spectroscopy, density functional theory
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:uu:diva-378748 (URN)10.1021/acsaem.8b00718 (DOI)000458706400060 ()
Available from: 2019-03-11 Created: 2019-03-11 Last updated: 2019-03-11Bibliographically approved
Tamm, A., Caro, M., Caro, A., Samolyuk, G., Klintenberg, M. & Correa, A. A. (2018). Langevin Dynamics with Spatial Correlations as a Model for Electron-Phonon Coupling. Physical Review Letters, 120(18), Article ID 185501.
Open this publication in new window or tab >>Langevin Dynamics with Spatial Correlations as a Model for Electron-Phonon Coupling
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2018 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 120, no 18, article id 185501Article in journal (Refereed) Published
Abstract [en]

Stochastic Langevin dynamics has been traditionally used as a tool to describe nonequilibrium processes. When utilized in systems with collective modes, traditional Langevin dynamics relaxes all modes indiscriminately, regardless of their wavelength. We propose a generalization of Langevin dynamics that can capture a differential coupling between collective modes and the bath, by introducing spatial correlations in the random forces. This allows modeling the electronic subsystem in a metal as a generalized Langevin bath endowed with a concept of locality, greatly improving the capabilities of the two-temperature model. The specific form proposed here for the spatial correlations produces a physical wave-vector and polarization dependency of the relaxation produced by the electron-phonon coupling in a solid. We show that the resulting model can be used for describing the path to equilibration of ions and electrons and also as a thermostat to sample the equilibrium canonical ensemble. By extension, the family of models presented here can be applied in general to any dense system, solids, alloys, and dense plasmas. As an example, we apply the model to study the nonequilibrium dynamics of an electron-ion two-temperature Ni crystal.

Place, publisher, year, edition, pages
American Physical Society, 2018
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-357017 (URN)10.1103/PhysRevLett.120.185501 (DOI)000432979900025 ()29775371 (PubMedID)
Available from: 2018-08-13 Created: 2018-08-13 Last updated: 2018-08-13Bibliographically approved
Phuyal, D., Jain, S. M., Philippe, B., Johansson, M. B., Pazoki, M., Kullgren, J., . . . Rensmo, H. (2018). The electronic structure and band interface of cesium bismuth iodide on a titania heterostructure using hard X-ray spectroscopy. Journal of Materials Chemistry A, 6(20), 9498-9505
Open this publication in new window or tab >>The electronic structure and band interface of cesium bismuth iodide on a titania heterostructure using hard X-ray spectroscopy
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2018 (English)In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, no 20, p. 9498-9505Article in journal (Refereed) Published
Abstract [en]

Bismuth halide compounds as a non-toxic alternative are increasingly investigated because of their potential in optoelectronic devices and their rich structural chemistry. Hard X-ray spectroscopy was applied to the ternary bismuth halide Cs3Bi2I9 and its related precursors BiI3 and CsI to understand its electronic structure at an atomic level. We specifically investigated the core levels and valence band using X-ray photoemission spectroscopy (PES), high-resolution X-ray absorption (HERFD-XAS), and resonant inelastic X-ray scattering (RIXS) to get insight into the chemistry and the band edge properties of the two bismuth compounds. Using these element specific X-ray techniques, our experimental electronic structures show that the primary differences between the two bismuth samples are the position of the iodine states in the valence and conduction bands and the degree of hybridization with bismuth lone pair (6s(2)) states. The crystal structure of the two layered quasi-perovskite compounds plays a minor role in modifying the overall electronic structure, with variations in bismuth lone pair states and iodine band edge states. Density Functional Theory (DFT) calculations are used to compare with experimental data. The results demonstrate the effectiveness of hard X-ray spectroscopies to identify element specific bulk electronic structures and their use in optoelectronic devices.

National Category
Materials Chemistry Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-357561 (URN)10.1039/c8ta00947c (DOI)000433427300020 ()
Funder
Swedish Research Council, 2014-6019Swedish Research Council, 2016-4524Swedish Energy Agency, P43549-1Swedish Foundation for Strategic Research , 15-0130Wallenberg Foundations, 2012.0031StandUp
Available from: 2018-08-20 Created: 2018-08-20 Last updated: 2019-02-19Bibliographically approved
Béland, L. K., Tamm, A., Mu, S., Samolyuk, G. D., Osetsky, Y. N., Aabloo, A., . . . Stoller, R. E. (2017). Accurate classical short-range forces for the study of collision cascades in Fe-Ni-Cr. Computer Physics Communications, 219, 11-19
Open this publication in new window or tab >>Accurate classical short-range forces for the study of collision cascades in Fe-Ni-Cr
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2017 (English)In: Computer Physics Communications, ISSN 0010-4655, E-ISSN 1879-2944, Vol. 219, p. 11-19Article in journal (Refereed) Published
Abstract [en]

The predictive power of a classical molecular dynamics simulation is largely determined by the physical validity of its underlying empirical potential. In the case of high-energy collision cascades, it was recently shown that correctly modeling interactions at short distances is necessary to accurately predict primary damage production. An ab initio based framework is introduced for modifying an existing embedded atom method FeNiCr potential to handle these short-range interactions. Density functional theory is used to calculate the energetics of two atoms approaching each other, embedded in the alloy, and to calculate the equation of state of the alloy as it is compressed. The pairwise terms and the embedding terms of the potential are modified in accordance with the ab initio results. Using this reparametrized potential, collision cascades are performed in Ni50Fe50, Ni80Cr20 and Ni33Fe33Cr33. The simulations reveal that alloying Ni and NiCr to Fe reduces primary damage production, in agreement with some previous calculations. Alloying Ni and NiFe to Cr does not reduce primary damage production, in contradiction with previous calculations.

Keywords
Force-field, Radiation damage, Alloys
National Category
Physical Sciences
Identifiers
urn:nbn:se:uu:diva-330532 (URN)10.1016/j.cpc.2017.05.001 (DOI)000407984100002 ()
Funder
Carl Tryggers foundation
Available from: 2017-10-04 Created: 2017-10-04 Last updated: 2018-09-28Bibliographically approved
Metsanurk, E., Tamm, A., Aabloo, A., Klintenberg, M. & Caro, A. (2017). Vacancies at the Cu-Nb semicoherent interface. Modelling and Simulation in Materials Science and Engineering, 25(2), Article ID 025012.
Open this publication in new window or tab >>Vacancies at the Cu-Nb semicoherent interface
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2017 (English)In: Modelling and Simulation in Materials Science and Engineering, ISSN 0965-0393, E-ISSN 1361-651X, Vol. 25, no 2, article id 025012Article in journal (Refereed) Published
Abstract [en]

We present the 0 K structures and formation energies for vacancy clusters of up to four vacancies and migration barriers for a single vacancy at a semicoherent Kurdjumov-Sachs Cu-Nb interface using ab initio calculations. Two main results emerge from this study, first that the predicted vacancy structure is compact, differing notoriously with predictions based on available empirical potentials, and second that vacancy clusters containing up to four vacancies have a smaller formation energy than monovacancy in bulk. Additionally, the binding energies show that the vacancy clusters are energetically stable for clusters having up to four vacancies. Nudged elastic band calculations of migration barriers show that the migration of a vacancy from one misfit dislocation intersection to another is highly improbable due to the high barriers. These findings suggest that at nonzero temperatures the interface will be preloaded with vacancy clusters with a relatively large capture radius for interstitials in the interface plane, implying that the semicoherent Cu-Nb interface could be a highly effective sink for point defects that form due to irradiation.

Keywords
vacancies, migration barrier, semicoherent meta-metal interface, density functional theory calculations
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-360222 (URN)10.1088/1361-651X/25/2/025012 (DOI)000425270700001 ()
Funder
EU, FP7, Seventh Framework Programme, 263273Carl Tryggers foundation Swedish Nuclear Fuel and Waste Management Company, SKB
Available from: 2018-09-11 Created: 2018-09-11 Last updated: 2018-09-11Bibliographically approved
Tamm, A., Samolyuk, G., Correa, A. A., Klintenberg, M., Aabloo, A. & Caro, A. (2016). Electron-phonon interaction within classical molecular dynamics. PHYSICAL REVIEW B, 94(2), Article ID 024305.
Open this publication in new window or tab >>Electron-phonon interaction within classical molecular dynamics
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2016 (English)In: PHYSICAL REVIEW B, ISSN 2469-9950, Vol. 94, no 2, article id 024305Article in journal (Refereed) Published
Abstract [en]

We present a model for nonadiabatic classical molecular dynamics simulations that captures with high accuracy the wave-vector q dependence of the phonon lifetimes, in agreement with quantum mechanics calculations. It is based on a local view of the e-ph interaction where individual atom dynamics couples to electrons via a damping term that is obtained as the low-velocity limit of the stopping power of a moving ion in a host. The model is parameter free, as its components are derived from ab initio-type calculations, is readily extended to the case of alloys, and is adequate for large-scale molecular dynamics computer simulations. We also show how this model removes some oversimplifications of the traditional ionic damped dynamics commonly used to describe situations beyond the Born-Oppenheimer approximation.

National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-300453 (URN)10.1103/PhysRevB.94.024305 (DOI)000379649300004 ()
Available from: 2016-08-09 Created: 2016-08-09 Last updated: 2016-08-09Bibliographically approved
Lindström, A., Mirbt, S., Sanyal, B. & Klintenberg, M. (2016). High resistivity in undoped CdTe: carrier compensation of Te antisites and Cd vacancies. Journal of Physics D: Applied Physics, 49(3), Article ID 035101.
Open this publication in new window or tab >>High resistivity in undoped CdTe: carrier compensation of Te antisites and Cd vacancies
2016 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 49, no 3, article id 035101Article in journal (Refereed) Published
Abstract [en]

In this paper, we focus on the high resistivity of intentionally undoped CdTe, where the most prevalent defects are Cd vacancies and Te antisites. Our calculated formation energies lead to the conclusion that the Fermi energy of undoped CdTe is at midgap due to carrier compensation of Te antisites and Cd vacancies, which explains the experimentally observed high resistivity. We use density functional theory with the hybrid functional of Heyd, Scuseria and Ernzerhof (HSE06) and show that the proper description of the native defects in general fails using the local density approximation (LDA) instead of HSE06. We conclude that LDA is insufficient to understand the high resistivity of undoped CdTe. We calculate the neutral and double acceptor state of the Te antisite to be intrinsic DX-centers.

Keywords
CdTe, Te antisite, Cd vacancy, defect formation energy
National Category
Other Physics Topics
Identifiers
urn:nbn:se:uu:diva-276799 (URN)10.1088/0022-3727/49/3/035101 (DOI)000368096300007 ()
Available from: 2016-02-16 Created: 2016-02-16 Last updated: 2017-11-30Bibliographically approved
Stoller, R. E., Tamm, A., Beland, L. K., Samolyuk, G. D., Stocks, G. M., Caro, A., . . . Wang, Y. (2016). Impact of Short-Range Forces on Defect Production from High Energy Collisions. Journal of Chemical Theory and Computation, 12(6), 2871-2879
Open this publication in new window or tab >>Impact of Short-Range Forces on Defect Production from High Energy Collisions
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2016 (English)In: Journal of Chemical Theory and Computation, ISSN 1549-9618, E-ISSN 1549-9626, Vol. 12, no 6, p. 2871-2879Article in journal (Refereed) Published
Abstract [en]

Primary radiation damage formation in solid materials typically involves collisions between atoms that have up to a few hundred keV of kinetic energy. Dining these collisions, the-distance between two colliding atoms can approach 0.05 nm. At such small atomic separations, force fields fitted-to equilibrium properties tend to significantly underestimate the potential-energy-of the colliding dieter. To enable molecular dynamics simulations of high-energy collisions, it is common practice to use a screened Coulomb, force field to describe the interactions and to smoothly join this to the equilibrium force field at a suitable interatomic spacing. However, there is,no accepted standard method for choosing the parameters used in the joining process, and our results prove that defect production is sensitive to how the force field's are linked. A new procedure is presented that involves the use of ab initio calculations to,determine the magnitude and spatial dependence of the pair interactions at intermediate distances, along with systematic criteria for choosing the joining parameters. Results are presented for the case of nickel, which demonstrate the use and validity of the procedure.

National Category
Atom and Molecular Physics and Optics Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-299736 (URN)10.1021/acs.jctc.5b01194 (DOI)000378016000034 ()27110927 (PubMedID)
Available from: 2016-07-26 Created: 2016-07-26 Last updated: 2017-11-28Bibliographically approved
Tamm, A., Aabloo, A., Klintenberg, M., Stocks, M. & Caro, A. (2015). Atomic-scale properties of Ni-based FCC ternary, and quaternary alloys. Acta Materialia, 99, 307-312
Open this publication in new window or tab >>Atomic-scale properties of Ni-based FCC ternary, and quaternary alloys
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2015 (English)In: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 99, p. 307-312Article in journal (Refereed) Published
Abstract [en]

The aim of this study is to characterize some atomic-scale properties of Ni-based FCC multicomponent alloys. For this purpose, we use Monte Carlo method combined with density functional theory calculations to study short-range order (SRO), atomic displacements, electronic density of states, and magnetic moments in equimolar ternary NiCrCo, and quaternary NiCrCoFe alloys. According to our study, the salient features for the ternary alloy are a negative SRO parameter between Ni-Cr and a positive between Cr-Cr pairs as well as a weakly magnetic state. For the quaternary alloy we predict negative SRO parameter for Ni-Cr and Ni-Fe pairs and positive for Cr-Cr and Fe-Fe pairs. Atomic displacements for both ternary and quaternary alloys are negligible. In contrast to the ternary, the quaternary alloy shows a complex magnetic structure. The electronic structure of the ternary and quaternary alloys shows differences near the Fermi energy between a random solid solution and the predicted structure with SRO. Despite that, the calculated EXAFS spectra does not show enough contrast to discriminate between random and ordered structures. The predicted SRO has an impact on point-defect energetics, electron-phonon coupling and thermodynamic functions and thus, SRO should not be neglected when studying properties of these two alloys.

Keywords
High entropy alloy, Density functional theory, Monte Carlo, Short-range order, Ni based alloys
National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:uu:diva-265669 (URN)10.1016/j.actamat.2015.08.015 (DOI)000362145400032 ()
Available from: 2015-11-04 Created: 2015-11-02 Last updated: 2017-12-01Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0001-6437-5889

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