Gain spectroscopy of continuous wave InGaN multi-quantum well laser diodes

A systematic study of the optical gain of continuous wave InGaN multiple quantum well laser diode wafers has been made using the variable excitation-stripe length method. Experimental evidence is given of stimulated emission enhanced by resonance between degenerate states and non-degenerate ones, which co-exist in quantum wells having spatial potential undulation due to considerable fluctuation of the InGaN composition.