Reduced spontaneous carrier lifetime in narrow stripe geometry GaAlAs DH lasers

We examined the dependence of spontaneous carrier lifetime on the stripe width in internally striped-planar GaAlAs DH lasers by measuring the turn-on delay time of lasing emission under step current injection. The measured carrier lifetime reduces in narrow stripe lasers. Reasonable interpretation of the results can be given by the increased carrier density at threshold which results from the increasing waveguide loss and the carrier loss by out-diffusion in narrow stripe lasers. There is also given another explicit explanation on the reduced carrier lifetime by using the rate equation.