论文标题
单轴压力引起的卤化物钙壶中的持续旋转纹理
Persistent spin textures in halide perovskites induced by uniaxial stress
论文作者
论文摘要
持续的自旋纹理对于旋转型的应用非常需要,因为它们可能允许长期载体旋转寿命。但是,它们也很少见,因为只有四个组可以容纳此类纹理,即使对于这四个组,持续的自旋纹理的出现就需要在耦合参数之间取得微妙的平衡,从而控制了自旋摩肌相互作用的强度。我们使用第一原理密度函数模拟来预测通过应用单轴应力实现这些理想的自旋纹理的可能性。混合有机无机钙钛矿mpsnbr $ _3 $(mp = ch $ _3 $ pH $ _3 $)是一种铁电性半导体,在其传导带中表现出持久的旋转纹理,并且最小值是其价值带的最小值Rashba类型。单轴应力的应用导致价带的逐渐演变从大多数是Rashba类型的旋转纹理到拉伸负荷下的持续性,以及在压缩负荷下纯粹的Rashba或持久性。我们还报告,该材料表现出柔韧性,橡胶样反应以及正和负压电常数。这种特性的组合可能会为灵活/橡胶旋转器设备创造机会。
Persistent spin textures are highly desirable for applications in spintronics as they may allow for long carrier spin lifetimes. However, they are also rare as only four point groups can host such textures, and even for these four groups, the emergence of persistent spin textures requires a delicate balance between coupling parameters, which control the strength of spin-momentum interactions. We use first-principles density functional simulations to predict the possibility of achieving these desirable spin textures through the application of uniaxial stress. Hybrid organic-inorganic perovskite MPSnBr$_3$ (MP = CH$_3$PH$_3$) is a ferroelectric semiconductor which exhibits persistent spin textures in the near to its conduction band minimum and mostly Rashba type in the vicinity of its valence band maximum. Application of uniaxial stress leads to the gradual evolution of the valence bands spin textures from mostly Rashba type to persistent ones under tensile load and to pure Rashba or persistent ones under compressive load. We also report that the material exhibits flexibility, rubber-like response, and both positive and negative piezoelectric constants. Combination of such properties may create opportunities for a flexible/rubbery spintronic devices.