Controlling photonic spin Hall effect via exceptional points
Controlling photonic spin Hall effect via exceptional points
复制标题
通过特异点控制光子自旋霍尔效应
DOI：
10.1103/physrevb.100.115429
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发表时间：
2019-07
影响因子：
3.7
通讯作者：
ong
中科院分区：
文献类型：
--
作者：
Zhou Xinxing;Lin Xiao;Xiao Zhicheng;Low Tony;Alu Andrea;Zhang Baile;Sun H;ong
光子自旋霍尔效应（SHE）的特点是入射光束在其偏振旋向性的驱动下发生自旋相关的横向位移，具有许多应用，包括精密计量和基于自旋的纳米光子器件。控制和增强光子SHE是高度期望的。然而，由于光的弱自旋-轨道相互作用，特别是对于具有光学损耗的系统，这样的目标仍然难以捉摸。在这里，我们揭示了一种灵活的方式来调制光子SHE通过特殊的点，通过利用在奇偶时间（PT）对称系统的平衡增益和损耗的横向位移。其物理机制与反射系数在异常点处的近零值和突变相位有关。我们发现，横向位移是在例外点为零，但它在很大程度上增强在其附近。此外，横向位移切换其符号跨越例外点，导致自发PT对称性破缺。由于异常点处横向位移的敏感性，我们的工作还表明，光子SHE可以实现一种精确的方法来探测光子系统中的异常点的位置。
The photonic spin Hall effect (SHE), featured by a spin-dependent transverse shift of an impinging optical beam driven by its polarization handedness, has many applications including precise metrology and spin-based nanophotonic devices. It is highly desirable to control and enhance the photonic SHE. However, such a goal remains elusive, due to the weak spin-orbit interaction of light, especially for systems with optical loss. Here we reveal a flexible way to modulate the photonic SHE via exceptional points, by exploiting the transverse shift in a parity-time (PT) symmetric system with balanced gain and loss. The underlying physics is associated with the near-zero value and abrupt phase jump of the reflection coefficients at exceptional points. We find that the transverse shift is zero at exceptional points, but it is largely enhanced in their vicinity. Moreover, the transverse shift switches its sign across the exceptional point, resulting from spontaneous PT-symmetry breaking. Due to the sensitivity of transverse shift at exceptional points, our work also indicates that the photonic SHE can enable a precise way to probe the location of exceptional point in photonic systems.
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影响因子：
8.6
作者：
Bender, CM;Boettcher, S
通讯作者：
Boettcher, S
影响因子：
8.6
作者：
Hirsch, JE
通讯作者：
Hirsch, JE
影响因子：
8.6
作者：
Onoda, M;Murakami, S;Nagaosa, N
通讯作者：
Nagaosa, N
DOI：
10.1117/12.798110
发表时间：
2008-08
期刊：
--
影响因子：
--
作者：
Michel Dyakonov
通讯作者：
Michel Dyakonov
影响因子：
3.6
作者：
Qin, Yi;Li, Yan;Gong, Qihuang
通讯作者：
Gong, Qihuang