Sub-100 W TEM00 bulk Nd:GdVO4 oscillator based on orthogonal thermal compensation

We present a Nd:GdVO4 bulk crystal oscillator with >70 WTEM00 laser output based on the orthogonal thermal compensation architecture. The asymmetry of thermo-optical effects in the anisotropic crystal was well compensated for, and the overall thermal load was also distributed to lower the crystal temperature and the risk of crystal fracture. At an output coupling of 60%, a 71.2 W, TEM00 laser output was achieved with 44% optical efficiency. The diffraction-limited beam quality was measured to be Mx2=1.01 and My2=1.04 in the orthogonal directions.