Beam quality of high power 800 nm broad-area laser diodes with 1 and 2 mu m large optical cavity structures

The beam quality of 800 nm AlGaAs/GaAsP broad-area (BA) laser diodes with l arge optical cavity (LOC) waveguide structures was studied under high power conditions. The LOC structures consist of a tensile-strained GaAsP single quantum well embedded in AlGaAs layers forming 1 and 2 mum thick waveguide cores. A low beam divergence of 51 degrees respectively 46 degrees (full wi dth at 1 /e(2) maximum) is obtained in fast axis direction. BA diode lasers with 2 mm cavity length and stripe widths of 60. 100 and 200 mum show beam quality factors M-2 along the slow axis of about 12, 16 and 35 at 2 W outp ut power, respectively. M-2 also weakly depends upon the waveguide width an d is slightly smaller for the 2 mum waveguide core if the stripe width is l ess than 100 mum. (C) 2001 Elsevier Science B.V. All rights reserved.