INTEGRATED OPTICAL CAVITY SEMICONDUCTOR LASERS

Abstract

The advent of the technology of optical or optoelectronic integrated circuits (OIC/OEIC) has enabled the integration oi a large number of existing optoelectronic devices onto a single piece of substrate. At the same time, integration is also opening new scopes for the design and implementation of new types of more complicated devices. Among them, the research on new semiconductor laser system with complex integrated cavity structures and capable of multiple functions is an area of particular interest. The study on this area of integrated cavity semiconductor lasers demands simulation tools which are capable of handling the diversity of complicated optical cavities typically encountered in these devices. A simulation model has been developed here which is capable of simulating an integrated cavity semiconductor laser with curved and branching cavity structures. The simulation model is mainly based on the Beam Propagation Method (BPM) which utilizes the Fast Fourier Transform extensively. It works by propagating a field through a cavity of arbitrary refractive index profile, and in several round trips through the cavity stabilizes into a self-consistent pattern that enables the far and near fields to be determined among the other characteristics of the laser model. A new integrated cavity semiconductor laser designed with beam scanning capability is also proposed. The design features a cavity structure containing a Y-junction and two interdigitated contact pads. The contact pads enable differential pumping to the device, through which the far field beam deflection can be controlled. Using the model developed earlier, the laser design is simulated and the results indicate a significant and potentially useful beam scanning capability for the new device.