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arXiv · 1911.10141

Crystal structure of the inversion-breaking metal Cd2Re2O7

M. R. Norman
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Abstract

Second harmonic generation (SHG) on the pyrochlore metal Cd2Re2O7 indicates the presence of three order parameters setting in below an inversion breaking transition. Here, we explore a possible structural explanation and relate it not only to the SHG data, but also to neutron and x-ray diffraction, where we find that such a structural scenario can explain certain reflection extinctions observed in single crystal x-ray data. From this analysis, we suggest future experiments that could be done to resolve this matter. Finally, we comment on the Landau-violating nature of the inversion breaking transition and its relation to similar phenomena observed in improper ferroelectrics.

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M. R. Norman. 2019-11-22. Crystal structure of the inversion-breaking metal Cd2Re2O7. https://doi.org/10.1103/physrevb.101.045117

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