Controlled far-field pattern selection in diffraction-coupled semiconductor laser arrays

摘要

A diffraction-coupled semiconductor laser array, and a related method for its operation, the array structure having a diffraction section that is electrically controllable independently of a waveguide section having multiple laser channels. Above a critical level of injected gain in the diffraction region, and with appropriate selection of channel and diffraction region dimensions, stable operation in the in-phase supermode results, with adjacent lasers operating in phase and a single-lobed far-field distribution pattern being produced. Below the critical level of injected gain, the out-of-phase supermode or multimode operation is favored and the narrow single peak of the far-field pattern is no longer present. This mode switching can be used to rapidly modulate operation of the array without directly switching it on and off.