Loss-free enhancement of photonic spin Hall shift by electromagnetically induced transparency
Phys. Rev. A 111, 063523 – Published 27 June, 2025
DOI: https://doi.org/10.1103/1c51-d7sz
Abstract
The photonic spin Hall effect, a result of spin-orbit interaction, has attracted significant interest because of its fundamental importance and potential applications. However, optical losses are ubiquitous, which hampers the enhancement of photonic spin Hall shift (PSHS). In this work, we consider an atomic medium that exhibits both absorption and transparency to investigate and mitigate the effects of loss on PSHS. We demonstrate that laser-induced coherence in an atomic medium, leading to electromagnetically induced transparency (EIT) at resonance, counteracts the detrimental effects of losses on the PSHS. Upon EIT at resonance in a coherent medium enclosed within dielectric slabs, zero reflectivity of the incident polarized state is restored at an incident angle defined by the conventional Brewster's angle to enhance PSHS. Moreover, the tunable refractive index of the atomic medium enables manipulation of PSHS without structural modifications with a tiny loss. Our proposed loss-free approach to PSHS may enable advanced optical sensing and other spin-based applications.
