Deep-oxide curved resonator for low-threshold AlGaAs–GaAs quantum well heterostructure ring lasers

Data are presented on curved-resonator AlGaAs–GaAs quantum well heterostructure laser diodes employing a deep-oxide guiding structure formed by a combination of impurity-induced layer disordering and native oxidation. Room-temperature, continuous wave (cw) threshold currents as low as ∼13 mA are measured for a ∼5 μm wide, 100 μm radius half-ring laser employing a deep-oxide structure. For similar 150 μm radius devices, cw threshold currents as low as ∼19 mA are observed (∼7 μm width), with total output powers exceeding 30 mW. Spectral data indicate single-mode operation over a large current range (25–100 mA). The low-threshold characteristics are attributed to the excellent current and optical confinement of the deep-oxide structure, combined with low edge scattering loss.