Inhomogeneous Polarization Transformation Reveals PT-Transition in non-Hermitian Optical Beam Shift
Abstract
Despite its non-Hermitian nature, the transverse optical beam shift exhibits both real eigenvalues and non-orthogonal eigenstates. To explore this unexpected similarity to typical PT (parity-time)-symmetric systems, we first categorize the entire parametric regime of optical beam shifts into Hermitian, PT-unbroken, and PT-broken phases. Besides experimentally unveiling the PT-broken regime, crucially, we illustrate that the observed PT-transition is rooted in the momentum-domain inhomogeneous polarization transformation of the beam. The correspondence with a typical non-Hermitian photonic system is further established. Our work not only resolves a longstanding fundamental issue in the field of optical beam shift but also puts forward the notion of novel non-Hermitian spin-orbit photonics: a new direction to study non-Hermitian physics through the optical beam shifts.
Keywords
Cite
@article{arxiv.2310.14210,
title = {Inhomogeneous Polarization Transformation Reveals PT-Transition in non-Hermitian Optical Beam Shift},
author = {Niladri Modak and Swain Ashutosh and Shyamal Guchhait and Sayan Ghosh and Ritwik Dhara and Jeeban Kumar Nayak and Sourin Das and Nirmalya Ghosh},
journal= {arXiv preprint arXiv:2310.14210},
year = {2024}
}