Characteristics of a high-power broad-area laser operating in a passively stabilized external cavity.

We narrowed the spectral bandwidth of our 2 W broad-area laser to 8+/-1 GHz with a coarse tunability of 12 nm centered near 790 nm in an external cavity. Our passively stabilized external cavity was designed for use with high-power semiconductor lasers. The cavity length and mount are modular with a fixed pivot point so that the optical elements can be changed to access a broad frequency spectrum and enable multiple applications. The bandwidth was observed to be dependent on the multimode transverse structure of the laser.