Spatially coherent radiation from an array of GaAs lasers

Abstract

Spatially coherent radiation from a monolithic array of three homostructure GaAs lasers is reported. The three lasers, with their mirror faces antireflection coated, are operated in external optical cavity built of spherical lenses and plane mirrors. The spatially coherent beam formation makes use of the Fourier transformation property of the internal lenses. The transverse mode control is performed by a spatial filter. The optical peak power at room temperature of the device was measured to be 5 W, three times the power of a single laser in the array. From the synthesized far-field distribution which was evaluated, we conclude that the laser radiation is of spatial coherence.