Clearing a Path for Light Through Non-Hermitian Media

Overview

Journal Nanophotonics

Publisher De Gruyter

Date 2024 Dec 5

PMID 39634953

Authors

Utsav D Dave

Gaurang R Bhatt

Janderson R Rodrigues

Ipshita Datta

Michal Lipson

Affiliations

Soon will be listed here.

Abstract

The performance of all active photonic devices today is greatly limited by loss. Here, we show that one can engineer a low loss path in a metal-clad lossy multi-mode waveguide while simultaneously achieving high-performance active photonic devices. We leverage non-Hermitian systems operating beyond the exceptional point to enable the redistribution of losses in a multi-mode photonic waveguide. Consequently, our multi-mode waveguide offers low propagation losses for fundamental mode while other higher order modes experience prohibitively high losses. Furthermore, we show an application of this non-Hermitian waveguide platform in designing power-efficient thermo-optic phase shifters with significantly faster response times than conventional silicon-based thermo-optic phase shifters. Our device achieves a propagation loss of less than 0.02 dB μm for our non-Hermitian waveguide-based phase shifters with high performance efficiency of ⋅ = 19.1 mW μs. In addition, our phase shifters have significantly faster response time (rise/fall time), ≈ 1.4 μs, compared to traditional silicon based thermo-optic phase shifters.

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