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arXiv · 2404.14116

Anomalous dispersion via dissipative coupling in a quantum well exciton-polariton microcavity

Dąbrówka Biegańska·Maciej Pieczarka·Christian Schneider·Sven Höfling·Sebastian Klembt·Marcin Syperek
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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.

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Dąbrówka Biegańska, Maciej Pieczarka, Christian Schneider, Sven Höfling, Sebastian Klembt, Marcin Syperek. 2024-04-22. Anomalous dispersion via dissipative coupling in a quantum well exciton-polariton microcavity. https://arxiv.org/abs/2404.14116

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