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Updated: May 28, 2025
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
Octahedral-Rotation-Induced, Antiferroelectric-like Double Hysteresis in Strained Perovskites
1Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States.
Abstract:
Antiferroelectrics, which host both polar and antipolar order parameters, are characterized by the double hysteresis loops which are advantageous for various applications such as high-density energy storage. In this study, we investigate the coupling between oxygen octahedral rotations and polarization in well-known perovskites, with a focus on SrTiO3. Using first-principles calculations and symmetry-adapted Landau-Ginzburg-Devonshire theory, we construct an energy landscape to analyze how this coupling shapes polarization-voltage hysteresis behavior. We show that tuning the relative strength of polar and rotational instabilities by exploiting epitaxial strain and layering leads to nontrivial hysteresis behavior. Consequently, the rotation coupling with polarization leads to an expanded search space of materials exhibiting antiferroelectric-like double hysteresis.
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