Electrical injection of a 440nm InGaN laser with lateral confinement by nanoporous-GaN

We report observations of lateral mode confinement by a tapering nanoporous-GaN layer in the n-side cladding of a blue-emitting InGaN laser diode grown on the semipolar (202¯1¯) plane of bulk GaN. Little additional confinement occurred in the transverse direction, and the nanoporous layer did not serve as a current aperture. Nanoporous-GaN, with Si-doping of 8x1018 cm−3 and 20% porosity had a bulk resistivity of 3 Ω-cm and a thermal conductivity of 4 W/m-K, in general agreement with data reported on c-plane VCSEL structures. An excess modal loss of 19 cm−1 was found.