Gain spectra of an (InGa)as single quantum well laser diode

A new method using the broad spectrum of a 10 fs Ti: sapphire laser is demonstrated for measuring the gain spectra of semiconductor lasers with high and quantitative accuracy. Results are shown for an edge-emitting ridge-waveguide In0.05Ga0.95As single quantum well (SQW) laser. The device is studied from the absorption regime up to the strong gain regime recording both, TE and TM polarizations. The experiments are compared to the predictions of a microscopic model based on the semiconductor Bloch equations including microscopic scattering and dephasing terms. A very good quantitative agreement is obtained.