Loiko P A, Yumashev K V, Kuleshov N V, Savitski V G, Calvez S, Burns D, Pavlyuk A A
Institute for Optical Materials and Technologies, Belarussian National Technical University, 65 Nezavisimosti Ave., bldg. 17, Minsk, 220013, Belarus.
Opt Express. 2009 Dec 21;17(26):23536-43. doi: 10.1364/OE.17.023536.
A comparative study of thermal lensing effect in diode laser pumped Ng- and Np-cut Nd:KGd(WO4)2 (KGW) laser crystals was performed for laser emission polarized along the principle refractive axis, Nm. The thermal lens in the Ng-cut Nd: KGW was found to be weakly astigmatic with a positive refractive power for both the Nm- and Np-directions. For Np -cut Nd:KGW, strong astigmatism was observed and the refractive powers in the Ng- and Nm-directions had opposing signs. The degree of astigmatism was found to be considerably weaker for the Ng-cut Nd:KGW in comparison with the Np-cut one: 0.35 dptr/(W/cm2) and 2.85 dptr/(W/cm2), respectively. The ratio of the thermal lens refractive powers in the planes parallel and perpendicular to the laser emission polarisation were measured as +1.4 and -0.425 for Ng- and Np-cut Nd:KGW respectively.
对沿主折射轴Nm偏振的激光发射，进行了二极管泵浦的Ng切割和Np切割Nd:KGd(WO4)2（KGW）激光晶体中热透镜效应的比较研究。发现Ng切割的Nd:KGW中的热透镜在Nm和Np方向均为弱像散且具有正屈光力。对于Np切割的Nd:KGW，观察到强像散，且Ng和Nm方向的屈光力具有相反的符号。发现Ng切割的Nd:KGW的像散程度与Np切割的相比要弱得多，分别为0.35 dptr/(W/cm2)和2.85 dptr/(W/cm2)。对于Ng和Np切割的Nd:KGW，平行和垂直于激光发射偏振平面的热透镜屈光力之比分别测量为+1.4和-0.425。
