Spin Hall effect of light in photon tunneling

TL;DR

This paper investigates the spin Hall effect of light during photon tunneling, revealing polarization-dependent shifts and conservation laws, with implications for nano-photonics.

Contribution

It demonstrates the polarization-dependent transverse shifts in photon tunneling and links them to angular momentum conservation, enhancing understanding of SHE in tunneling.

Findings

Transverse shifts depend on polarization and can be modulated by refractive index gradients.

Spin Hall effect in photon tunneling is enhanced compared to conventional refraction.

Polarization-dependent shifts are governed by angular momentum conservation laws.

Abstract

We resolve the breakdown of angular momentum conservation on two-dimensional photon tunneling by considering spin Hall effect (SHE) of light. This interesting effect manifests itself as polarization-dependent transverse shifts for a classic wave packet tunneling through a prism-air-prism barrier. For a certain circularly polarized component, the transverse shifts can be modulated by altering the refractive index gradient associated with the two prisms. We find that the SHE in conventional beam refraction can be evidently enhanced via photon tunneling mechanism. The polarization-dependent transverse shift is governed by the total angular momentum conservation law, while the polarization-dependent angular shift is governed by the total linear momentum law. These findings open the possibility for developing new nano-photonic devices and can be extrapolated to other physical systems.