Landau quantisation of photonic spin Hall effect in monolayer black phosphorus
Landau quantisation of photonic spin Hall effect in monolayer black phosphorus
复制标题
单层黑磷中光子自旋霍尔效应的朗道量子化
DOI：
10.1515/nanoph-2019-0424
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发表时间：
2020
期刊：
影响因子：
7.5
通讯作者：
Xiaoying Zhou
中科院分区：
文献类型：
--
作者：
Guangyi Jia;Geng Li;Yan Zhou;Xianglong Miao;Xiaoying Zhou
摘要光子自旋霍尔效应（PSHE）是控制光子自旋态和开发基于自旋光学的下一代光子器件的一个很有前途的候选者。本文研究了垂直磁场对单层黑磷（BP）表面PSHE的影响。结果表明，由于外磁场B引起的朗道能级分裂，面内和横向自旋相关位移都被量子化，并呈现振荡模式.随着B的增强，由于LL间距的增大，自旋霍尔位移的振荡周期逐渐增大。相反，对于固定磁场，随着LL指数的增加，LL间距越来越小，自旋霍尔位移的振荡周期随着光子能量的增加而逐渐减小.此外，它可能是由于协同作用的内在各向异性，高结晶度，和量化引起的局部减少跳动样复杂的导电性的BP膜，巨大的自旋霍尔位移，数百倍的入射波长，在横向和面内方向获得。这些明确地证实了外部磁场对PSHE的强烈影响，并为理解各向异性二维原子晶体中丰富的磁光输运性质提供了重要的见解。
Abstract The photonic spin Hall effect (PSHE) is a promising candidate for controlling the spin states of photons and exploiting next-generation photonic devices based on spinoptics. Herein, the influences of a perpendicular magnetic field on the PSHE appearing on the surface of monolayer black phosphorus (BP) are investigated. Results reveal that both the in-plane and transverse spin-dependent shifts are quantised and show an oscillating pattern due to the splitting of Landau levels (LLs) induced by the external magnetic field B. And the oscillation period of spin Hall shifts gradually increases with strengthening B because of the increase of LL spacings. By contrast, for a fixed magnetic field, as the LL spacings become smaller and smaller with increasing the LL index, the oscillation period of spin Hall shifts gradually decreases as the photonic energy increases. Moreover, it is possibly due to the synergistic role of intrinsic anisotropy, high crystallinity, and quantisation-incurred localised decreases in beating-like complex conductivities of the BP film, giant spin Hall shifts, hundreds of times of the incident wavelength, are obtained in both transverse and in-plane directions. These unambiguously confirm the strong impact of the external magnetic field on the PSHE and shed important insights into understanding the rich magneto-optical transport properties in anisotropic two-dimensional atomic crystals.