Thermal lensing in Yb:KLu(WO4)2 crystals cut along the optical indicatrix axes

Thermal lensing is studied in Yb:KLu(WO4)2 crystals cut along the three optical indicatrix axes, Np, Nm and Ng. The cut along the Ng-axis is the only one that provides a pure positive thermal lens with the sensitivity factors M = 3.5 and 2.8 m−1 W−1 (wp = 100 μm) for the mg- and pg-planes, respectively, and a low astigmatism degree, S/M < 20%. Both Np-cut and Nm-cut crystals produce different-signed lens with at least six-times stronger astigmatism. This behavior is related to the anisotropy of the photo-elastic effect. A CW Yb:KLu(WO4)2 microchip laser delivering a maximum output power of 992 mW at 1051 nm with a slope efficiency of 40%, and possessing low spatial distortions of the laser beam and M2 < 1.1, is realized on the basis of Ng-cut crystal.

[1]  Xavier Mateos,et al.  Growth and properties of KLu(WO4)2, and novel ytterbium and thulium lasers based on this monoclinic crystalline host , 2007 .

[2]  M. Vitiello,et al.  Quantum cascade lasers: a versatile source for precise measurements in the mid/far-infrared range , 2013 .

[3]  Xavier Mateos,et al.  Structural redetermination, thermal expansion and refractive indices of KLu(WO4)2 , 2006 .

[4]  Xavier Mateos,et al.  Crystal growth, spectroscopic studies and laser operation of Yb3+-doped potassium lutetium tungstate , 2006 .

[5]  P. Loiko,et al.  Detailed characterization of thermal expansion tensor in monoclinic KRe(WO4)2 (where Re = Gd, Y, Lu, Yb) , 2011 .

[6]  Bruce D. Sinclair,et al.  Guiding effects in Nd:YVO/sub 4/ microchip lasers operating well above threshold , 1999 .

[7]  Valentin Petrov,et al.  Efficient continuous-wave and Q-switched operation of a diode-pumped Yb:KLu(WO4)2 laser with self-Raman conversion. , 2005, Optics letters.

[8]  B. Sinclair.  Frequency-doubled microchip lasers , 1999 .

[9]  J. Zayhowski,et al.  Single-frequency microchip Nd lasers. , 1989, Optics letters.

[10]  Karen Willcox,et al.  Kinetics and kinematics for translational motions in microgravity during parabolic flight. , 2009, Aviation, space, and environmental medicine.

[11]  M. Pollnau,et al.  Double Tungstate Lasers: From Bulk Toward On-Chip Integrated Waveguide Devices , 2007, IEEE Journal of Selected Topics in Quantum Electronics.

[12]  N. Hodgson,et al.  Laser Resonators and Beam Propagation , 2005 .

[13]  P. Loiko,et al.  Thermal lensing in Nm-cut monoclinic Tm:KLu(WO4)2 laser crystal , 2013 .

[14]  S. Li,et al.  Thermal lensing in an end-pumped Yb:KGW slab laser with high power single emitter diodes. , 2008, Optics express.

[15]  Konstantin V. Yumashev,et al.  14 W high-efficiency diode-pumped cw Yb:KGd(WO4)2 laser with low thermo-optic aberrations , 2013 .

[16]  Xavier Mateos,et al.  Efficient high-power laser operation of Yb:KLu(WO4)2 crystals cut along the principal optical axes. , 2007, Optics letters.

[17]  N V Kuleshov,et al.  Thermal lens study in diode pumped Ng- and Np-cut Nd:KGd(WO4)2 laser crystals. , 2009, Optics express.

[18]  V. Petrov,et al.  Thermal properties of monoclinic KLu(WO4)2 as a promising solid state laser host. , 2008, Optics express.

[19]  Patrick Georges,et al.  On thermal effects in solid state lasers: the case of ytterbium-doped materials , 2006 .

[20]  Katrin Paschke,et al.  Diode-pumped gigahertz femtosecond Yb:KGW laser with a peak power of 3.9 kW. , 2010, Optics express.

[21]  A. Demidovich,et al.  Laser operation and Raman self-frequency conversion in Yb:KYW microchip laser , 2002 .

[22]  F. Balembois,et al.  Thermal lensing measurements in diode-pumped Yb-doped GdCOB, YCOB, YSO, YAG and KGW , 2003 .

[23]  G. Erbert,et al.  Passively mode-locked Yb:KLu(WO4)2 oscillators. , 2005, Optics express.

[24]  V. Pasiskevicius,et al.  Laser performance and thermal lensing in high-power diode-pumped Yb:KGW with athermal orientation , 2006 .