A theoretical analysis of self-sustained pulsation phenomena in narrow-stripe semiconductor lasers

Phenomena of the self-sustained pulsation are being utilized for reduction of the excess noise in the semiconductor injection laser. The generating mechanism of the self-sustained pulsation in semiconductor lasers having a narrow strip structure was theoretically analyzed. The pulsation is generated by the existence of the active region as well as the saturable absorbing regions located outside of the active region. The width of the active region (stripe width) should be narrower than several microns in a GaAs laser to get the pulsation. The gain guiding or the antiindex guiding with narrower active region is profitable to get higher operation keeping the pulsation.>