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arXiv · 2505.01792

Landau theory description of autferroicity

Jun-Jie Zhang·Boris I. Yakobson·Shuai Dong
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Abstract

Autferroics, recently proposed as a sister branch of multiferroics, exhibit strong intrinsic magnetoelectricity, but ferroelectricity and magnetism are mutually exclusive rather than coexisting. Here, a general model is considered based on the Landau theory, to clarify the distinction between multi and autferroics by qualitative change-rotation in Landau free energy landscape and in particular phase mapping. The TiGeSe$_3$ exemplifies a factual material, whose first-principles computed Landau coefficients predict its autferroicity. Our investigations pave the way for an alternative avenue in the pursuit of intrinsically strong magnetoelectrics.

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Jun-Jie Zhang, Boris I. Yakobson, Shuai Dong. 2025-05-03. Landau theory description of autferroicity. https://doi.org/10.1103/physrevlett.134.216801

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