Large and nonlinear electric field response in a two-dimensional ferroelectric Rashba material  

具有非线性和强电场响应的二维铁电Rashba材料

作　　者：Li Sheng Xiaomin Fu Chao Jia Xingxing Li Qunxiang Li 圣利;付晓敏;贾超;李星星;李群祥(中国科学技术大学精准智能化学重点实验室,安徽合肥230026;中国科学技术大学化学物理系,安徽合肥230026;中国科学技术大学合肥微尺度物质科学国家研究中心,安徽合肥230026;中国科学技术大学合肥国家实验室,安徽合肥230088)

机构地区：[1]Key Laboratory of Precision and Intelligent Chemistry,University of Science and Technology of China,Hefei 230026,China [2]Department of Chemical Physics,University of Science and Technology of China,Hefei 230026,China [3]Hefei National Research Center for Physical Sciences at the Microscale,University of Science and Technology of China,Hefei 230026,China [4]Hefei National Laboratory,University of Science and Technology of China,Hefei 230088,China

出　　处：《中国科学技术大学学报》2024年第6期8-11,21,I0009,共6页JUSTC

基　　金：supported by the National Natural Science Foundation of China(22322304,22273092,22373095);the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0450101);the Innovation Program for Quantum Science and Technology(2021ZD0303306);the USTC Tang Scholar;The authors wish to acknowledge the Supercomputing Center of the USTC for providing computational resources.

摘　　要：The achievement of electrical spin control is highly desirable.One promising strategy involves electrically mod-ulating the Rashba spin orbital coupling effect in materials.A semiconductor with high sensitivity in its Rashba constant to external electric fields holds great potential for short channel lengths in spin field-effect transistors,which is crucial for preserving spin coherence and enhancing integration density.Hence,two-dimensional(2D)Rashba semiconductors with large Rashba constants and significant electric field responses are highly desirable.Herein,by employing first-principles calculations,we design a thermodynamically stable 2D Rashba semiconductor,YSbTe_(3),which possesses an indirect band gap of 1.04 eV,a large Rashba constant of 1.54 eV·Åand a strong electric field response of up to 4.80 e·Å^(2).In particular,the Rashba constant dependence on the electric field shows an unusual nonlinear relationship.At the same time,YSbTe_(3)has been identified as a 2D ferroelectric material with a moderate polarization switching energy barrier(~0.33 eV per formula).By changing the electric polarization direction,the Rashba spin texture of YSbTe_(3)can be reversed.These out-standing properties make the ferroelectric Rashba semiconductor YSbTe_(3)quite promising for spintronic applications.自旋调控是自旋电子学面临的一个关键问题,其中一种有效的方法是通过外部电场调控材料的Rashba自旋轨道耦合效应。设计具有大Rashba常数和强电场响应的二维Rashba半导体对于发展短沟道长度的自旋场效应晶体管,提高晶体管自旋相干性和集成密度至关重要。本研究采用第一性原理计算,成功设计了一种热力学稳定的二维Rashba半导体YSbTe_(3),其间接带隙为1.04 eV,Rashba常数为1.54 eV·Å,并具有强的电场响应,高达4.80 e·Å^(2)。YSbTe_(3)的Rashba系数随电场变化呈现异常的非线性关系。此外,YSbTe_(3)也是一种二维铁电材料,其铁电极化翻转势垒较低(约0.33 eV每化学式)。通过改变电极化方向,可以反转YSbTe_(3)的Rashba自旋纹理。这些优异的性质使得铁电Rashba半导体YSbTe_(3)在自旋电子学领域具有广泛的应用前景。

关 键 词：computational chemistry Rashba effect FERROELECTRICS SPINTRONICS 

分 类 号：O469[理学—凝聚态物理]