Long wavelength triangular shaped waveguide diode ring laser with dry etched facets

Summary form only given. Semiconductor ring lasers in unidirectional operation set up a traveling wave inside the cavity, thus avoiding the standing wave spatial hole burning effects relevant in DFB and Fabry-Perot lasers. This results in high spectral purity and hence lowering intensity noise by reducing the mode partition noise. Among the triangular square and circular ring lasers reported, the first mentioned geometry is attractive because of its inherent output coupler and demonstrated power efficiency. We report record low threshold current and large side mode suppression ratio (SMSR) for long wavelength triangular ring InGaAsP QW lasers.