Coherent, monolithic two-dimensional (10×10) laser arrays using grating surface emission

Abstract

Two-dimensional, coherent AlGaAs laser arrays consisting of 100 (10×10) active elements have been fabricated using single quantum well laser structures. A surface relief grating is used both for feedback and outcoupling. The elements of the array are index-guided ridge lasers. In one array design, the elements are coupled laterally by evanescent field overlap while in the second design, the coupling is by Y branches. Longitudinal coherence is achieved by injection coupling. The far field, emanating from a 60 μm by 5 mm aperture, measures 0.01°×1°. Both types of arrays emit more than 1 W peak power. The mode spectrum of the emitted power is contained in a ∼2–3 Å wavelength interval at ∼1 W.