Analysis of Impulse Responses Characteristics of an Optical Delayed Feedback Semiconductor Laser

Abstract

Abstract Impulse response characteristics of a semiconductor laser with weak optical feedback (OF) is studied. Equations about the amplitude and frequency responses of the laser under the current modulation condition are deduced. We demonstrate theoretically that the equations are the function of the modulation frequency, optical feedback level and delayed time. We give the impulse response function under the jump signal modulation condition with OF and without OF, this is helpful for digital laser communications. The numerical results demonstrated that OF can make the laser obtain the enhancement of the modulation response and bandwidth and can reduce the frequency respond in the some parameters range. OF can enhance gently the relaxation oscillation of the foreland or the tail of the impulse response signal under the weak OF case while the oscillation can be enhanced sensitivity to the modulation under the larger OF case