Electrically switchable hidden spin polarization in antiferroelectric crystals
Electrically switchable hidden spin polarization in antiferroelectric crystals
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反铁电晶体中可电切换的隐藏自旋极化
DOI：
10.1103/physrevb.102.184104
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发表时间：
2020-11-09
影响因子：
3.7
通讯作者：
Luo, Jun-Wei
中科院分区：
文献类型：
--
作者：
Guan, Shan;Luo, Jun-Wei
隐藏自旋极化（HSP）出现在中心对称晶体中，由于每个局部扇区缺乏反转对称性，在实际空间中可以观察到可见的自旋分裂。从紧密结合模型出发，我们引入了非对称反铁电晶体（AFE）作为一类新的功能材料，可以表现出强的局部自旋极化。这种AFE晶体基本上可以分为面内和面外AFE构型，并且可以通过电场可逆地切换到铁电相以表现全局自旋分裂，从而实现对自旋相关性质的非易失性电控制。基于第一性原理计算，我们预测了一种新发现的二维材料五层LiBiO$_2$的AFE相中可以实现强热稳定性。进一步讨论了QL-LiBiO$_2$的自发电极化（$\sim$ 0.3 nC/m）、跃迁势垒和可调自旋极化。
Hidden spin polarization (HSP) emerges in centrosymmetric crystals where visible spin splittings in the real space can be observed because of the lack of inversion symmetry in each local sector. Starting from tight-binding models, we introduce nonsymmorphic antiferroelectric (AFE) crystals as a new class of functional materials that can exhibit strong local spin polarization. Such AFE crystals can be basically classified as in-plane and out-of-plane AFE configurations, and can be reversibly switched to the ferroelectric phase by an electric field to manifest global spin splittings, enabling a nonvolatile electrical control of spin-dependent properties. Based on first-principle calculations, we predict the realization of strong HSP in the AFE phase of a newly-discovered two-dimensional materials, quintuple-layer (QL) LiBiO$_2$. Furthermore, the spontaneous electric polarization ($\sim$ 0.3 nC/m) and the transition barrier as well as the tunable spin polarization of QL-LiBiO$_2$ are discussed.