All-solid-state CW Nd:KGd(WO4)2 self-Raman laser at 561 nm by intracavity sum-frequency mixing of fundamental and first-Stokes wavelengths

We report for the first time an efficient continuous wave (CW) laser emission at 561 nm by sum-frequency mixing of the fundamental and first-Stokes fields generated within an Nd:KGd(WO 4 ) 2 self-Raman laser. Intracavity sum-frequency mixing with LiB 3 O 5 (LBO) nonlinear crystal yielded 570 mW of visible yellow-green emission; the output power stability over 4 h is better than 4.6%. The laser beam quality M 2 factors are 1.54 and 2.13 in both horizontal and vertical dimensions respectively.