An Analytical Solution of the Lateral Current Spreading and Diffusion Problem in Narrow Oxide Stripe (GaAI)As/GaAs DH Lasers

G. Lengyel, University of Rhode Island
Peter Meissner, Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut, HHI
Erwin Patzak, Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut, HHI
K. H. Zschauer, Siemens AG


An exact solution is presented to the problem of lateral current spreading in the resistive layer of oxide stripe geometry DH lasers. The two-dimensional Laplace equation was solved by conformal mapping using the Schwarz-Christoffel transformation. The diffusion equation containing nonlinear recombination terms was solved numerically. Computed examples demonstrate that the customary one-dimensional treatment of the resistive layer or the assumption of constant current density under the stripe contact are not always justified, particularly for narrow stripe widths and low specific resistivities. This region of low values of the resistivity and stripe width, however, is of great practical interest in the design of oxide stripe lasers having high thermal stability and kink-free characteristics. © 1982 IEEE