LAUSR

Continuous-wave (CW) pumped lasers with device areas below 1 μm2 constitute a key step to meeting the energy efficiency requirement for on-chip optical communications. However, a debate about whether a submicron device size and low threshold can be simultaneously satisfied has persisted owing to insurmountable radiation losses when approaching the optical diffraction limit. Herein, we demonstrate a record-small CW optically pumped perovskite laser with a device area of 0.65 μm2 . We find the thresholds of submicron lasers can be lower than those of several-micron counterparts, and ascribe it to the enlarged group refractive index and modal confinement resulting from the enhanced exciton-photon coupling. Moreover, the operation temperature is elevated to 150 K through the reduction in heat generation. Our findings unveil the potential of exciton-polaritons in laser miniaturization, providing an alternative for developing low-threshold semiconductor lasers without artificial optical cavities, to approach the optical diffraction limit. This article is protected by copyright. All rights reserved.