Detection of electron magnetic circular dichroism signals under zone axial diffraction geometry
2016 (English)In: Ultramicroscopy, ISSN 0304-3991, E-ISSN 1879-2723, Vol. 169, 44-54 p.Article in journal (Refereed) Published
EMCD (electron magnetic circular dichroism) technique provides us a new opportunity to explore magnetic properties in the transmission electron microscope. However, specific diffraction geometry is the major limitation. Only the two-beam and three-beam case are demonstrated in the experiments until now. Here, we present the more general case of zone axial (ZA) diffraction geometry through which the EMCD signals can be detected even with the very strong sensitivity to dynamical diffraction conditions. Our detailed calculations and well-controlled diffraction conditions lead to experiments in agreement with theory. The effect of dynamical diffraction conditions on EMCD signals are discussed both in theory and experiments. Moreover, with the detailed analysis of dynamical diffraction effects, we experimentally obtain the separate EMCD signals for each crystallographic site in Y3Fe5O12, which is also applicable for other materials and cannot be achieved by site-specific EMCD and XMCD technique directly. Our work extends application of more general diffraction geometries and will further promote the development of EMCD technique.
Place, publisher, year, edition, pages
2016. Vol. 169, 44-54 p.
EMCD, Zone axial diffraction geometry, Dynamical diffraction effect
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:uu:diva-305320DOI: 10.1016/j.ultramic.2016.07.005ISI: 000383819100006PubMedID: 27448200OAI: oai:DiVA.org:uu-305320DiVA: diva2:1037597
FunderSwedish Research CouncilGöran Gustafsson Foundation for promotion of scientific research at Uppala University and Royal Institute of TechnologyThe Swedish Foundation for International Cooperation in Research and Higher Education (STINT)