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arXiv · 1105.2043

First-principles investigation of morphotropic transitions and phase-change functional responses in BiFeO3-BiCoO3 multiferroic solid solutions

Oswaldo Diéguez·Jorge Íñiguez
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Abstract

We present an ab initio study of the BFCO solid solution formed by multiferroics BiFeO3 (BFO) and BiCoO3 (BCO). We find that BFCO presents a strongly discontinuous morphotropic transition between BFO-like and BCO-like ferroelectric phases. Further, for all compositions such phases remain (meta)stable and retain well-differentiated properties. Our results thus suggest that an electric field can be used to switch between these structures, and show that such a switching involves large phase-change effects of various types, including piezoelectric, electric, and magnetoelectric ones.

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Oswaldo Diéguez, Jorge Íñiguez. 2011-05-10. First-principles investigation of morphotropic transitions and phase-change functional responses in BiFeO3-BiCoO3 multiferroic solid solutions. https://doi.org/10.1103/physrevlett.107.057601

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