Tang Tingting, Li Jie, Luo Li, Sun Ping, Zhang Yanfen
Opt Express. 2017 Feb 6;25(3):2347-2354. doi: 10.1364/OE.25.002347.
Spin Hall effect of light (SHEL) is prosperous in precision metrology and quantum information processing. In normal situations, the inevitable loss of material will greatly weaken SHEL, which is a major constraint to its potential applications. We first report the loss enhanced SHEL through epsilon and mu-near-zero (EMNZ) metamaterial slab by anisotropic configuration of epsilon and mu tensors. It is verified that the loss of EMNZ metamaterial can effectively enlarge the splitting between right-circularly polarized (RCP) and left-circularly polarized light (LCP) components of linear polarized light even when the incident angle is much larger than critical angle. Calculation results show that when the imaginary part of permeability's vertical component is equal to 0.1, a flat-top transverse shift peak can be observed which remains unchanged for different vertical component of permeability and thickness of EMNZ metamaterial. In this case the maximum transverse shift of left-circularly polarized light can be increased to 24.676 micrometers by EMNZ metamaterial loss without any amplification method. Meanwhile, the transverse shifts of RCP (LCP) light can be modulated flexibly by EMNZ metamaterial loss. Therefore the loss enhanced SHEL makes quantum devices applicable which paves the way towards on-chip and inter-chip optical circuitry.
光自旋霍尔效应（SHEL）在精密计量学和量子信息处理领域蓬勃发展。在正常情况下，材料不可避免的损耗会极大地削弱SHEL，这是其潜在应用的一个主要限制因素。我们首次报道了通过对介电常数张量和磁导率张量进行各向异性配置，利用介电常数和磁导率近零（EMNZ）超材料平板实现损耗增强的SHEL。实验证实，即使入射角远大于临界角，EMNZ超材料的损耗也能有效扩大线偏振光的右旋圆偏振（RCP）和左旋圆偏振光（LCP）分量之间的分裂。计算结果表明，当磁导率垂直分量的虚部等于0.1时，可以观察到一个平顶横向位移峰值，对于不同的磁导率垂直分量和EMNZ超材料厚度，该峰值保持不变。在这种情况下，通过EMNZ超材料损耗，左旋圆偏振光的最大横向位移可以增加到24.676微米，无需任何放大方法。同时，RCP（LCP）光的横向位移可以通过EMNZ超材料损耗灵活调制。因此，损耗增强的SHEL使量子器件得以应用，为片上和芯片间光电路铺平了道路。
