High brightness index-guided parabolic bow-tie laser arrays

This letter describes a novel 980-nm parabolic bow-tie laser array (PBTLA) that is suitable for high-power and high-brightness operation. Output powers in excess of 2.5 W/facet pulsed in a 1/spl deg/ (lateral) beam, less than twice the diffraction limit, corresponding to 275 MW/spl middot/cm/sup -2//spl middot/sr/sup -1/ brightness, have been measured without the use of external lenses from uncoated PBTLAs fabricated in-house (top metal contact surface area/spl sim/0.1 mm/sup 2/). Experimental results presented in this letter indicate that coherence effects are significant in the operation of such devices. Theoretical models based on the simple diffraction theory and on the coupled-mode theory have been used to interpret the experimental results.