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arXiv · 1907.06259

Frustrated Dipole Order Induces Noncollinear Proper Ferrielectricity in Two Dimensions

Ling-Fang Lin·Yang Zhang·Adriana Moreo·Elbio Dagotto·Shuai Dong
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Abstract

Within Landau theory, magnetism and polarity are homotopic, displaying a one-to-one correspondence between most physical characteristics. However, despite widely reported noncollinear magnetism, spontaneous noncollinear electric dipole order as ground state is rare. Here a dioxydihalides family is predicted to display noncollinear ferrielectricity, induced by competing ferroelectric and antiferroelectric soft modes. This intrinsic noncollinearity of dipoles generates unique physical properties, such as $\mathbb{Z}_2\times\mathbb{Z}_2$ topological domains, atomic-scale dipole vortices, and negative piezoelectricity.

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Ling-Fang Lin, Yang Zhang, Adriana Moreo, Elbio Dagotto, Shuai Dong. 2019-07-14. Frustrated Dipole Order Induces Noncollinear Proper Ferrielectricity in Two Dimensions. https://doi.org/10.1103/physrevlett.123.067601

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