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arXiv · 1105.2676

High-pressure phase transitions in BiFeO3: hydrostatic vs. non-hydrostatic conditions

Mael Guennou·Pierre Bouvier·Raphaël Haumont·Gaston Garbarino·Jens Kreisel
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Abstract

We report high-pressure x-ray diffraction experiments on BiFeO3 (BFO) single crystals in diamond-anvil cells up to 14 GPa. Two data sets are compared, one in hydrostatic conditions, with helium used as pressure-transmitting medium, and the other in non-hydrostatic conditions, with silicon oil as pressure-transmitting medium. It is shown that the crystal undergoes different phase transitions in the two cases, highlighting the high sensitivity of BFO to non-hydrostatic stress. Consequences for the interpretation of high-pressure structural studies are discussed.

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Mael Guennou, Pierre Bouvier, Raphaël Haumont, Gaston Garbarino, Jens Kreisel. 2011-05-13. High-pressure phase transitions in BiFeO3: hydrostatic vs. non-hydrostatic conditions. https://doi.org/10.1080/01411594.2011.552014

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