Anomalous dispersion via dissipative coupling in a quantum well exciton-polariton microcavity
Abstract
Although energy level repulsion is typically observed in interacting quantum systems, non-Hermitian physics predicts the effect of level attraction, which occurs when significant energy dissipation is present. Here, we show a manifestation of dissipative coupling in a high-quality AlGaAs-based polariton microcavity, where two polariton branches attract, resulting in an anomalous, inverted dispersion of the lower branch in momentum dispersion. Using angle-resolved photoluminescence measurements we observe the evolution of the level attraction with exciton-photon detuning, leading to changes in anomalous dispersion shape within a single sample. The dissipative coupling is explained by the interaction with an indirect exciton, acting as a highly dissipative channel in our system, and the observed dispersions are well captured within a phenomenological model. Our results present a new mechanism of dissipative coupling in light-matter systems and offer a tunable and well-controlled AlGaAs-based platform for engineering the non-Hermitian and negative mass effects in polariton systems.
Keywords
Cite
@article{arxiv.2404.14116,
title = {Anomalous dispersion via dissipative coupling in a quantum well exciton-polariton microcavity},
author = {Dąbrówka Biegańska and Maciej Pieczarka and Christian Schneider and Sven Höfling and Sebastian Klembt and Marcin Syperek},
journal= {arXiv preprint arXiv:2404.14116},
year = {2024}
}