All-optical delay line based on a cavity soliton laser with injection

The motion and position of cavity solitons in a vertical-cavity surface-emitting laser with optical injection are investigated. Spatial variations of the phase of the injected field are considered in the form of sinusoidal and triangular modulations. We show how the velocity, distance traveled, and final position of the cavity solitons can be controlled by varying the slope of the phase modulations and the response time of the semiconductor medium. Numerical simulations demonstrate the feasibility of an all-optical delay line in a cavity soliton laser. Merging of cavity solitons is observed when they collide at modulation maxima and is shown to be beneficial in the operation of the delay line. The merging and consequent emission of pulsed and localized light is explained in terms of violation of energy balance for soliton systems in the presence of injection and dissipation.