论文标题
野外诱导的超快调制在室温下，铁电$α$ - gete（111）
Field-induced ultrafast modulation of Rashba coupling at room temperature in ferroelectric $α$-GeTe(111)
论文作者
论文摘要
Rashba材料已成为原型SpinTronics设备中旋转转换的理想操场。其中，$α$ gete（111）是一种非中心的铁电（Fe）半导体，强烈的自旋轨道相互作用会引起巨大的Rashba耦合。最近，它的室温铁电是基于可切换极化的新型高能非挥发性存储装置的途径。目前，基于电场的应用，通过使用飞秒（FS）的光脉冲，需要探索该时间表上可能控制铁电性的可能控制的脉冲脉冲可以优于写作和阅读过程。在这里，我们使用时间和角度分辨光发射光谱（TR-ARPES）探测$α$ gete（111）电子带结构的室温瞬态动力学。我们的实验表明，通过表面光伏（SPV）在FS时间尺度上介导的RASHBA耦合的超快调制，即增加对应于晶格失真的13％增强的增加。这为控制Fe两极分化的途径打开了$α$ gete（111）和量子异质结构中的Fe半导体材料的途径。
Rashba materials have appeared as an ideal playground for spin-to-charge conversion in prototype spintronics devices. Among them, $α$-GeTe(111) is a non-centrosymmetric ferroelectric (FE) semiconductor for which a strong spin-orbit interaction gives rise to giant Rashba coupling. Its room temperature ferroelectricity was recently demonstrated as a route towards a new type of highly energy-efficient non-volatile memory device based on switchable polarization. Currently based on the application of an electric field, the writing and reading processes could be outperformed by the use of femtosecond (fs) light pulses requiring exploration of the possible control of ferroelectricity on this timescale. Here, we probe the room temperature transient dynamics of the electronic band structure of $α$-GeTe(111) using time and angle-resolved photoemission spectroscopy (tr-ARPES). Our experiments reveal an ultrafast modulation of the Rashba coupling mediated on the fs timescale by a surface photovoltage (SPV), namely an increase corresponding to a 13 % enhancement of the lattice distortion. This opens the route for the control of the FE polarization in $α$-GeTe(111) and FE semiconducting materials in quantum heterostructures.
