Self-modulation of injection laser emission intensity due to external optical feedback

Low frequency oscillations in the radiation intensity of injection lasers caused by the introduction of optical feedback are investigated on a dual Al sub x Ca sub 1-x As-GaAs buried stripe heterolaser producing several spatial modes at lambda approximately 0.86 um. The experimental setup is described, and the oscillations in intensity of the laser radiation are analyzed and found to be of two types: sinusoidal high frequency oscillations with frequencies F sub 0, F sub 1, etc., and low frequency relaxation-type oscillations with frequencies f.