High d/gamma values in diode laser structures for very high power

Abstract

Record values for the rollover power and rollover linear power densities of 9xx nm devices, obtained by simultaneous scaling of length and d/Γ, are reported. The values for d/Γ lay in the range 0.8 μm to 1.2 μm with corresponding cavity lengths from 3.5 mm to 5 mm. The transversal structures were asymmetric, with a higher refractive index on the n side. An optical trap was helpful in reducing the radiation extension on the p side and the overall thickness. The highest rollover linear power densities were 244 mW/μm for structures without an optical trap and 290 mW/μm for those that included an optical trap