Microstadium single-nanowire laser

We report room-temperature lasing in an optically pumped single-nanowire stadium microresonator. The photoluminescence from a chemically synthesized GaN nanowire is coupled and confined in a silicon-nitride stadium microcavity. Photoluminescence spectroscopy exhibits lasing at 372 nm with a lasing threshold of 1536 kW cm2. We compute a Q factor of ∼3500 for the microstadium single-nanowire structure using finite-difference time-domain simulation. The successful demonstration of this hybrid structure using bottom-up and top-down approaches represents a significant step toward high-density integration of functional building blocks for an ultracompact nanophotonic circuit.