Dynamics of self focusing in stripe-geometry semiconductor lasers

Abstract
The dielectric-waveguide properties of stripe-geometry semiconductor lasers can be deduced by measuring the output-beam shape in the vicinity of the laser facet. Time-resolved near-field measurements have been made on 20μm wide SiO2insulated-stripe lasers and the results used to calculate the time-varying gain and refractive-index profiles during the intial part of a lasing pulse. The effects of self focusing due to the transverse distribution of injected carriers can clearly be observed.