Tamm-Plasmon Exciton-Polaritons in Single-Monolayered CsPbBr_3 Quantum Dots at Room Temperature

摘要

Constructing polaritonic devices in monolithic, ultra-compact photonicarchitectures with monolayer-featured exciton-emitters is decisive to exploitthe coherent superposition between entangled photonic and excitoniceigenstates for potential realizations of optical nonlinearities, macroscopiccondensations, and superfluidity. Here, a feasible strategy for exciton-polaritonformations is demonstrated by implementing a Tamm-plasmon (TP)polaritonic device with the active material composed of single-monolayeredperovskite (CsPbBr_3) quantum dots (QDs). The metallic character of theTP configuration is able to concentrate its resonance mode into a confinedregion beyond the diffraction limit, which highly overlaps, both spatiallyand spectrally, with the single-monolayered CsPbBr3 QDs embedded inside.The mode volume of the device is hence reduced dramatically, leading toan enhanced light–matter coupling strength for the polaritonic emission atroom temperature. In particular, it is found that the dispersion relation ofthe TP polaritonic device is tunable by detuning the excitonic and photoniceigenmodes and that the polariton–polariton interaction energy is stronglydependent on the polariton’s spin state. The presented strategy is a determinantstep toward the realization of strong light–matter coupling and polaritonspintronics in the CsPbBr_3 QDs with a single-monolayered feature.