The electric-field-induced phase transition from antipolar to polar structures is at the heart of antiferroelectricity. We demonstrate direct evidence of antiferroelectricity by applying a strong electric field to two antipolar crystals of squaric acid (SQA) and 5,5′-dimethyl-2,2′-bipyridinium chloranilate. The field-induced polarization of SQA is quite large and reasonably explained by the theoretically calculated polarization on the hydrogen-bonded sheet sublattice. The pseudo-tetragonal lattice of SQA permits unique switching topologies that produce two different ferroelectric phases of low and high polarizations. By tilting the applied field direction, the electrical switching mechanism can be attributed to a 90° rotation of the sheet polarization. From the viewpoint of applications, the strong polarization, high switching field, and quite slim hysteresis observed in the polarization versus electric field curve for SQA are advantageous for excellent-efficiency energy storage devices.

中文翻译：

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氢键有机反铁电材料中的低能量损耗的强极化开关

电场引起的从反极性到极性结构的相变是反铁电的核心。我们通过对两个方酸（SQA）和5,5'-二甲基-2,2'-联吡啶鎓氯胺酸盐的反极性晶体施加强电场来证明反铁电的直接证据。SQA的场致极化非常大，并且可以通过理论计算得出的氢键合板子晶格上的极化来合理解释。SQA的伪四边形晶格允许产生两种不同的低极化和高极化铁电相的独特开关拓扑。通过倾斜施加的场方向，可以将电开关机构归因于薄片极化的90°旋转。从应用的角度来看，强极化，高开关场，SQA的电场相对于电场的曲线对于效率极高的能量存储设备是有利的。