Surface plasmon coupling regulated CsPbBr₃ perovskite lasers in a metal-insulator-semiconductor structure

A strong coupling effect often occurs between a metal and semiconductor, so micro/nano-lasers based on surface plasmons can break through the optical diffraction limit and realize unprecedented linear and nonlinear enhancement of optical processes. Hence, metal-insulator-semiconductor (M-I-S) structures based on perovskite materials were explored to design optoelectronic devices. Herein, we constructed an Ag/SiO₂/CsPbBr₃ hybrid structure to generate surface plasmon coupled emission between the metal and CsPbBr₃ perovskite. Combined with experimental characterization and COMSOL Multiphysics software simulations, the best enhancement for CsPbBr₃ radiative recombination efficiencies can be achieved with a 10 nm-thickness of the SiO₂ layer and 80 nm-thickness of the Ag metal film, further verified by optimizing the thickness of the SiO₂ layer above the Ag metal film. In this state, the laser threshold can be as low as 0.138 μW with a quality (Q) factor of up to 3907 under optical pumping, which demonstrate a significant step toward practical applications in biological technology, chemical identification, and optical interconnections of information transmission.