High-performance photonic spin Hall effect in anisotropic epsilon-near-zero metamaterials
Huifeng Chen, Daozhao Guan, Wenguo Zhu, Huadan Zheng, Jianhui Yu, Yongchun Zhong, Zhe Chen
Abstract
A high-performance photonic spin Hall effect is demonstrated in an anisotropic epsilon-near-zero (ENZ) metamaterial based on the wave-vector-varying Pancharatnam–Berry phase. The giant out-of-plane anisotropy of ENZ metamaterial induces strong spin–orbit coupling. With a small incident angle, photons with opposite spins move along opposite transverse directions gradually. After transmitting through a submicrometer thick ENZ metamaterial, the spin photons are fully separated with a spin separation of 2.7 times beam waist and transmittance of 70.1%, allowing a figure of merit <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>F</mml:mi> </mml:math> up to 1.9. A practical ENZ metamaterial consisting of an Ag nanorod array is proposed, whose figure of merit is still up to 0.006. This high-performance photonic spin Hall effect provides an integrated and practical way for the development of spin-photonic devices.