论文标题
平面外高温铁磁单层CRSCL，具有较大的垂直压电响应
Out-of-plane high-temperature ferromagnetic monolayer CrSCl with large vertical piezoelectric response
论文作者
论文摘要
对于二维（2D）材料，对于多功能超薄压电设备的应用，高度希望具有大型平面压电响应的压电性铁磁（PFM）。在这里，我们预测Janus Monolayer CRSCL是一个平面外铁磁（FM）半导体，具有较大的垂直压电响应和较高的居里温度。预测的平面压电系数系数$ d_ {31} $是-1.58 pm/v，它高于大多数2D材料的材料（比较$ d_ {31} $的绝对值）。较大的平面压力电离对电子相关性和双轴应变具有鲁棒性，证实了大$ d_ {31} $的可靠性。计算的结果表明，拉伸应变有利于高咖喱温度，较大的磁各向异性能量（MAE）和大$ d_ {31} $。最后，通过比较cryx（y = s; x = cl，br i）和cryx（y = o; x = f，cl，br）的$ d_ {31} $，我们得出结论，$ d_ {31} $的大小与x和y atom的电负性差异很正式相关。这样的发现可以为设计具有较大垂直压电响应的2D压电材料提供宝贵的指南。
For two-dimensional (2D) material, piezoelectric ferromagnetism (PFM) with large out-of-plane piezoresponse is highly desirable for multifunctional ultrathin piezoelectric device application. Here, we predict that Janus monolayer CrSCl is an out-of-plane ferromagnetic (FM) semiconductor with large vertical piezoelectric response and high Curie temperature. The predicted out-of-plane piezoelectric strain coefficient $d_{31}$ is -1.58 pm/V, which is higher than ones of most 2D materials (compare absolute values of $d_{31}$). The large out-of-plane piezoelectricity is robust against electronic correlation and biaxial strain, confirming reliability of large $d_{31}$. Calculated results show that tensile strain is conducive to high Curie temperature, large magnetic anisotropy energy (MAE) and large $d_{31}$. Finally, by comparing $d_{31}$ of CrYX (Y=S; X=Cl, Br I) and CrYX (Y=O; X=F, Cl, Br), we conclude that the size of $d_{31}$ is positively related to electronegativity difference of X and Y atoms. Such findings can provide valuable guidelines for designing 2D piezoelectric materials with large vertical piezoelectric response.
