Relaxation oscillations in single-frequency InAsSb narrow band-gap lasers

Relaxation oscillations have been investigated in A(3)B(5) narrow band-gap semiconductor lasers. Based on wideband intensity noise measurements, the relaxation oscillation frequency has been observed up to 2 GHz for a 2 mW cw single-frequency InAsSb laser at a 3.4 mu m wavelength. Laser parameters that influence the bandwidth, including the photon Lifetime tau(p), the differential gain A and the spontaneous recombination lifetime tau(s) were calculated from experimental data obtained at 95 K. We found tau(p) in the range 0.7-1.9 ps, A was estimated to be (4.7-7.3)x 10(-6) cm(-3) s(-1) and tau(s) =2.5-6.9 ns. Relaxation oscillations,occurred beyond the modulation bandwidth required for typical applications of antimonide lasers in spectroscopy. (C) 1998 American Institute of Physics.