Stable Green Perovskite Vertical-Cavity Surface-Emitting Lasers on Rigid and Flexible Substrates

Solution processed thin film organo-metal halide perovskites are gaining attention as attractive material prospects for low cost visible and near-infrared lasers while benefiting from recent large investments in photovoltaics of this micro/nanocrystalline material class. A number of reports have demonstrated optically pumped laser action in various optical resonator configurations at comparative low thresholds that might ultimately be compatible with corresponding injection currents required for junction lasers. One major question, however, is the inherent material robustness and stability of the perovskites under what are much higher optical and electronic excitation conditions than encountered in photovoltaics, yet typical in the technologically mature epitaxially grown III–V compound semiconductor lasers. Here we assess CH(NH2)2PbBr3 (FAPbBr3) solid thin films embedded within two sputtered planar dielectric HfO2/SiO2 distributed Bragg reflectors (DBRs) in green perovskite vertical-cavity surface-emitting lasers (PeVCSELs). The high quality factor single mode resonator (Q ∼ 1420) enables us to reach lasing threshold at low optical pumping (∼18.3 μJ/cm2) while delivering a temporally and spatially well-defined output beam. The device fabrication approach automatically self-encapsulates the perovskite active layer from the ambient. We report here achieving a device lasing lifetime for up to 20 h (∼108 laser shots) at room temperature under sustained illumination of 355 nm pulsed laser excitations (0.34 ns, 1 kHz). We also show how this PeVCSEL microfabrication route can be generally adapted to many substrates, specifically demonstrating a green perovskite thin film surface-emitting laser on a flexible polymer substrate.