An analytical solution of the lateral current spreading and diffusion problem in narrow oxide stripe /GaAl/As/GaAs DH lasers

The solution of the two-dimensional Laplace equation by conformal mapping using the Schwarz-Christoffel transformation provides an exact solution to the problem of lateral current spreading in the resistive layer of oxide-stripe geometry DH lasers, where the diffusion equation containing nonlinear recombination terms is solved numerically. It is demonstrated by the examples computed that one-dimensional treatments of the resistive layer, or the assumption of constant current density under the stripe contact, are not justified for the cases of narrow stripe widths and low specific resistivity values which are of interest in the design of oxide stripe lasers exhibiting high thermal stability and kink-free characteristics.