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arXiv · 0810.2332

Theory of magnetic field-induced metaelectric critical end point in BiMn$_2$O$_5$

Gun Sang Jeon·Jin-Hong Park·Kee Hoon Kim·Jung Hoon Han
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Abstract

A recent experiment on the multiferroic BiMn$_2$O$_5$ compound under a strong applied magnetic field revealed a rich phase diagram driven by the coupling of magnetic and charge (dipolar) degrees of freedom. Based on the exchange-striction mechanism, we propose here a theoretical model with the intent to capture the interplay of the spin and dipolar moments in the presence of a magnetic field in BiMn$_2$O$_5$. Experimentally observed behavior of the dielectric constants, magnetic susceptibility, and the polarization is, for the most part, reproduced by our model. The critical behavior observed near the polarization reversal $(P=0)$ point in the phase diagram is interpreted as arising from the proximity to the critical end point.

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Gun Sang Jeon, Jin-Hong Park, Kee Hoon Kim, Jung Hoon Han. 2008-10-13. Theory of magnetic field-induced metaelectric critical end point in BiMn$_2$O$_5$. https://doi.org/10.1103/physrevb.79.104437

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