Observation of Rydberg exciton polaritons and their condensate in a perovskite cavity

Abstract

The condensation of half-light half-matter exciton polaritons in semiconductor optical cavities is a striking example of macroscopic quantum coherence in a solid-state platform. Quantum coherence is possible only when there are strong interactions between the exciton polaritons provided by their excitonic constituents. Rydberg excitons with high principal value exhibit strong dipole–dipole interactions in cold atoms. However, polaritons with the excitonic constituent that is an excited state, namely Rydberg exciton polaritons (REPs), have not yet been experimentally observed. Here, we observe the formation of REPs in a single crystal CsPbBr3 perovskite cavity without any external fields. These polaritons exhibit strong nonlinear behavior that leads to a coherent polariton condensate with a prominent blue shift. Furthermore, the REPs in CsPbBr3 are highly anisotropic and have a large extinction ratio, arising from the perovskite’s orthorhombic crystal structure. Our observation not only sheds light on the importance of many-body physics in coherent polariton systems involving higher-order excited states, but also paves the way for exploring these coherent interactions for solid-state quantum optical information processing.

Spin-orbit–coupled exciton-polariton condensates in lead halide perovskites

“…The two polariton modes are orthogonally polarized (figs. S11 and S12), in agreement with a report by Bao et al ( 25 ) on a CsPbBr 3 microcavity. Note that these authors did not observe diabolic points, spin textures, or phase transition into competing condensates.…”

Polarization‐Sensitive Halide Perovskites for Polarized Luminescence and Detection: Recent Advances and Perspectives

“…Bao et al. [ 61 ] reported the strong linearly polarized PL in CsPbBr 3 single‐crystal perovskite cavity without any external fields, which was assigned to the anisotropic orthorhombic crystal structure of CsPbBr 3 .…”

Transient circular dichroism and exciton spin dynamics in all-inorganic halide perovskites

“…In contrast to the hybrid organic–inorganic perovskites, CsPbX 3 show distinct properties, such as excellent environmental stability and robust excitonic effects 7 , 12 , and would be ideal for spin-optoelectronic and quantum-optic applications. For instance, Bose–Einstein condensation and lasing of exciton polaritons in the CsPbX 3 microcavities have been demonstrated at room temperature recently 7 , 12 , 24 , 25 . Introducing spin functionalities in such system will facilitate the development of spin-based quantum logic devices 26 – 30 .…”