Axicon based conical resonators with high power copper vapor laser

作者：Singh Bijendra^*; Subramaniam V V; Daultabad S R; Chakraborty Ashim

来源：Review of Scientific Instruments, 2010, 81(7): 073110.

DOI：10.1063/1.3457847

We report for the first time the performance of axicon based conical resonators (ABCRs) in a copper vapor laser, with novel results. The unstable conical resonator comprising of conical mirror (reflecting axicon) with axicon angle similar to pi/18, cone angle similar to 160 degrees, and a convex mirror of 60 cm radius of curvature was effective in reducing the average beam divergence to similar to 0.15 mrad (similar to 25 fold reduction compared to standard multimode plane-plane cavity) with output power of similar to 31 W. Extraction efficiency of similar to 50%-60% and beam divergence of <1 mrad was achieved in other stable ABCR configurations using flat and concave mirrors with the axicon. This is a significant improvement compared to 4-5 mrad normally observed in conventional stable resonators in copper vapor lasers. The conical resonators with copper vapor laser provide high misalignment tolerance beta similar to 4-5 mrad where beta is the tilt angle of the conical mirror from optimum position responsible for similar to 20% decline in laser power. The depth of focus d was similar to three times larger in case of conical resonator as compared to that of standard spherical unstable resonator under similar beam divergence and focusing conditions.

• 出版日期2010-7