Abstract

Although energy level repulsion is typically observed in interacting quantum systems, non-Hermitian physics predicts level attraction when significant energy dissipation is present. This work demonstrates dissipative coupling in a high-quality AlGaAs-based polariton microcavity, where two polariton branches attract and produce an anomalous inverted lower-branch dispersion in momentum space. Angle-resolved photoluminescence measurements reveal how the effect evolves with exciton-photon detuning, including a change in anomalous dispersion shape within a single sample. The dissipative channel is attributed to an indirect exciton state, and the measured dispersions are captured by a phenomenological model.

Abstract

Although energy level repulsion is typically observed in interacting quantum systems, non-Hermitian physics predicts level attraction when significant energy dissipation is present. This work demonstrates dissipative coupling in a high-quality AlGaAs-based polariton microcavity, where two polariton branches attract and produce an anomalous inverted lower-branch dispersion in momentum space. Angle-resolved photoluminescence measurements reveal how the effect evolves with exciton-photon detuning, including a change in anomalous dispersion shape within a single sample. The dissipative channel is attributed to an indirect exciton state, and the measured dispersions are captured by a phenomenological model.

Abstract

Although energy level repulsion is typically observed in interacting quantum systems, non-Hermitian physics predicts level attraction when significant energy dissipation is present. This work demonstrates dissipative coupling in a high-quality AlGaAs-based polariton microcavity, where two polariton branches attract and produce an anomalous inverted lower-branch dispersion in momentum space. Angle-resolved photoluminescence measurements reveal how the effect evolves with exciton-photon detuning, including a change in anomalous dispersion shape within a single sample. The dissipative channel is attributed to an indirect exciton state, and the measured dispersions are captured by a phenomenological model.

Abstract

Although energy level repulsion is typically observed in interacting quantum systems, non-Hermitian physics predicts level attraction when significant energy dissipation is present. This work demonstrates dissipative coupling in a high-quality AlGaAs-based polariton microcavity, where two polariton branches attract and produce an anomalous inverted lower-branch dispersion in momentum space. Angle-resolved photoluminescence measurements reveal how the effect evolves with exciton-photon detuning, including a change in anomalous dispersion shape within a single sample. The dissipative channel is attributed to an indirect exciton state, and the measured dispersions are captured by a phenomenological model.