Brightness enhancement of continuous-wave beams using a diamond Raman laser

摘要

Brightness enhancement of high power quasi-continuous-wave beams is investigated in a diamond Raman laser as a function of the input beam quality. Up to 389 W of 1240 nm output is generated with a 78.2% linear slope efficiency and 52.5% overall conversation efficiency. For an M2 = 3.3 pump, the output beam quality factor of M2 = 1.08 was obtained, yielding a brightness enhancement factor of 3.7. Higher brightness enhancement factors are predicted when using lower beam quality pumps provided that a minimum input brightness is attained. The results point to new ways of creating brighter laser beams from high power lasers having degraded beam quality.