Room-Temperature Near-Infrared High-Q Perovskite Whispering-Gallery Planar Nanolasers

Near-infrared (NIR) solid-state micro/nanolasers are important building blocks for true integration of optoelectronic circuitry.1 Although significant progress has been made in III–V nanowire lasers with achieving NIR lasing at room temperature,2−4 challenges remain including low quantum efficiencies and high Auger losses. Importantly, the obstacles toward integrating one-dimensional nanowires on the planar ubiquitous Si platform need to be effectively tackled. Here we demonstrate a new family of planar room-temperature NIR nanolasers based on organic–inorganic perovskite CH3NH3PbI3-aXa (X = I, Br, Cl) nanoplatelets. Their large exciton binding energies, long diffusion lengths, and naturally formed high-quality planar whispering-gallery mode cavities ensure adequate gain and efficient optical feedback for low-threshold optically pumped in-plane lasing. We show that these remarkable wavelength tunable whispering-gallery nanolasers can be easily integrated onto conductive platforms (Si, Au, indium tin oxide, and so forth). Our findings open up a new class of wavelength tunable planar nanomaterials potentially suitable for on-chip integration.