Modeling of and Experimentation on Vertical Cavity Surface Emitting Laser Arrays

TLDR: In this article, a 2D antiguided vertical cavity surface emitting laser (VCSEL) array was studied by the 3D bidirectional beam propagation method, and conditions were found for favorable lasing of the in-phase mode providing high laser beam quality.

Abstract: Modal behavior of a 2D (square lattice geometry) antiguided vertical cavity surface emitting laser (VCSEL) array was studied by the 3D bidirectional beam propagation method. Above-threshold operation of leaky modes was simulated using multiple iterations. In addition, a method based on functions of Krylov's sub- space was developed to find the number of array optical modes in a VCSEL array with gain and index distribu- tions established by the oscillating mode. In calculations, both Fourier and space variable descriptions of beam propagation were combined. Analysis of an effective-index approximation is made, and explicit expressions are derived for the effective index and blue shift of the laser frequency. Conditions are found for favorable lasing of the in-phase mode providing high laser beam quality. The 2D antiguided array results from shifting the cavity resonance between the element and interelement regions and is fabricated by selective chemical etching and two-step metalorganic chemical vapor deposition (MOCVD) growth. In-phase and out-of-phase array mode operation is observed from top-emitting rectangular arrays as large as 400 elements, depending on the interele- ment width, in good agreement with theory. The experimentally realized set of laser arrays of variable size was studied numerically.