Modal dynamics and noise of vertical-cavity surface-emitting lasers

This work demonstrates simulations of single mode surface relief VCSELs and compares with multimode VCSELs without surface relief. This work has developed an advanced, yet efficient, time-domain model for VCSELs to be able to numerically study the different effects of modal competition. The spatially quasi-3-D model accounts for important interrelated physical processes, which dramatically change the distributions of the modal optical fields, carrier density, and temperature. The model has been extended to include the random fluctuations of the processes so that the noise properties can also be simulated. To demonstrate the capabilities of the model, a simulation of the high-speed operation and noise performance of three single and three multimode VCSELs of wavelength 850 nm, having oxide aperture diameters of 4, 6, and 8 μm is demonstrated. The "inverted" surface relief technique is applied to achieve single mode operation. The relief diameter for the three respective single mode devices are 2.5, 3.5, and 4 μm.