Analysis of transverse-mode control in vertical-cavity surface-emitting lasers using a convex mirror

We theoretically studied the modal discrimination of vertical-cavity surface-emitting lasers (VCSELs) using a convex mirror and a long spacer. Our model is based on a three-dimentional beam propagation method (BPM). Carrier density distribution in the active layer is calculated by solving the rate equation including transverse carrier diffusion. Results indicate that the side-mode suppression ratio (SMSR) and single fundamental mode output power would be improved by applying a convex mirror with a suitable curvature.