Electrically pumped elliptical microresonator lasers with unidirectional emission

An AlGaInAs/InP elliptical resonator microlaser laterally confined by a BCB layer, with an output waveguide connected to the minor axis is demonstrated experimentally and investigated numerically. A major axis of 12μm and an aspect ratio of 1.2 elliptical microlaser with a 2μm wide output waveguide is fabricated by planar techniques. Lasing spectra with a longitudinal mode wavelength interval of 10.6nm, which agreement with the 2-D finite element method (FEM) simulation results, and side mode suppression ratios (SMSR) of 30dB are observed. Numerical simulation results indicate that the elliptical resonator with the output waveguide has better single-mode property and high mode Q factor. The results indicate that elliptical resonator microlaser with an output waveguide can operate in unidirectional emission.