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Structural dichroism in the antiferromagnetic insulating phase of V$_2$O$_3$

C. Meneghini·S. Di Matteo·C. Monesi·T. Neisius·L. Paolasini·S. Mobilio·C. R. Natoli·P. A. Metcalf·J. M. Honig
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Abstract

We performed near-edge x-ray absorption spectroscopy (XANES) at V K edge in the antiferromagnetic insulating (AFI) phase of a 2.8% Cr-doped V$_2$O$_3$ single crystal. Linear dichroism of several percent is measured in the hexagonal plane and found to be in good agreement with ab-initio calculations based on multiple scattering theory. This experiment definitively proves the structural origin of the signal and therefore solves a controversy raised by previous interpretations of the same dichroism as non-reciprocal. It also calls for a further investigation of the role of the magnetoelectric annealing procedure in cooling to the AFI phase.

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C. Meneghini, S. Di Matteo, C. Monesi, T. Neisius, L. Paolasini, S. Mobilio, C. R. Natoli, P. A. Metcalf, J. M. Honig. 2005-06-17. Structural dichroism in the antiferromagnetic insulating phase of V$_2$O$_3$. https://doi.org/10.1103/physrevb.72.033111

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