Quantized Microcavity Polariton Lasing Based on InGaN Localized Excitons

TL;DR

Researchers demonstrated room-temperature polariton lasing in quantized energy states using InGaN quantum wells, enabling control of macroscopic quantum effects.

Contribution

Achieved quantized polariton lasing at room temperature using localized excitons in InGaN/GaN quantum wells with a parabolic potential well.

Findings

Room-temperature polaritons with 61 meV Rabi splitting were obtained using InGaN/GaN quantum wells.

Quantized energy sublevels with a maximum spacing of 11.3 meV were observed in the SHO states.

Coherent polariton lasing was achieved in the ground state with coherence confirmed via interference and g(2)(τ) measurements.

Abstract

Exciton–polaritons, which are bosonic quasiparticles with an extremely low mass, play a key role in understanding macroscopic quantum effects related to Bose–Einstein condensation (BEC) in solid-state systems. The study of trapped polaritons in a potential well provides an ideal platform for manipulating polariton condensates, enabling polariton lasing with specific formation in k-space. Here, we realize quantized microcavity polariton lasing in simple harmonic oscillator (SHO) states based on spatial localized excitons in InGaN/GaN quantum wells (QWs). Benefiting from the high exciton binding energy (90 meV) and large oscillator strength of the localized exciton, room-temperature (RT) polaritons with large Rabi splitting (61 meV) are obtained in a strongly coupled microcavity. The manipulation of polariton condensates is performed through a parabolic potential well created by optical pump control. Under the confinement situation, trapped polaritons are controlled to be distributed in the selected quantized energy sublevels of the SHO state. The maximum energy spacing of 11.3 meV is observed in the SHO sublevels, indicating the robust polariton trapping of the parabolic potential well. Coherent quantized polariton lasing is achieved in the ground state of the SHO state and the coherence property of the lasing is analyzed through the measurements of spatial interference patterns and g(2)(τ). Our results offer a feasible route to explore the manipulation of macroscopic quantum coherent states and to fabricate novel polariton devices towards room-temperature operations.

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