Abstract

Phase-locked arrays of index-guided diode lasers (≥8 elements) are of interest as sources of high powers in stable diffraction-limited beams. Some evanescently coupled arrays^1,2 have demonstrated single diffraction-limited beam operation close to lasing threshold. However, for drive levels exceeding (1.5-1.7) X threshold the beam invariably broadens due to gain spatial hole burning so that at (3-4) times threshold the beams are 2.5-4 times the diffraction limit, making them of little use for systems employing beam-forming optics. For evanescently coupled arrays (≥8 elements) the highest reported powers in nearly diffraction- limited beams are 60-70 mW.^1,2

© 1988 Optical Society of America