Non-Hermitian guided modes and exceptional points using loss-free negative-index materials

Abstract

We analyze the guided modes in coupled waveguides made of negative-index materials without gain or loss. We show that it supports non-Hermitian phenomenon on the existence of guided mode versus geometric parameters of the structure. The non-Hermitian effect is different from parity-time (PT) symmetry, and can be explained by a simple coupled-mode theory with an anti-PT symmetry. The existence of exceptional points and slow-light effect are discussed. This work highlights the potential of loss-free negative-index materials in the study of non-Hermitian optics.

References in corpus (4)

• Making Sense of Non-Hermitian Hamiltonians
• Guided Modes in Negative Refractive Index Waveguides
• Light stops at exceptional points
• Revisit the Poynting vector in PT-symmetric coupled waveguides