Disk and ring microcavity lasers and their concentric coupling

Structures of concentric microdisk and rings were studied theoretically and experimentally. A three-dimensional (3-D) model was developed, emphasizing the possibility of coupling several concentric microresonators. The 3-D analysis resulted in closed-form analytic expressions for the six field components from which the limitations and necessary conditions for concentric coupling were derived. We emphasized the important differences between our results and the predictions of the more commonly used two-dimensional models-the latter are failing to predict the concentric coupling actual feasibility. Finally, we present experimental results of coupled ring vertical-cavity surface-emitting lasers, revealing a good match to the 3-D model predictions.