Yb:GdVO_4晶体的光谱及激光损伤阈值

The Spectrum Properties and the Laser Damage Threshold of Yb:GdVO_4 Crystals

采用提拉法(Czochralski)生长出优质的GdVO4和Yb:GdVO4晶体,其中纯GdVO4晶体具有较高的透过率,可达81%.晶体在室温下的偏振吸收光谱与非偏振荧光光谱表明,Yb:GdVO4晶体是一种具有较大的吸收半峰宽和荧光半峰宽的激光晶体,分别为44～52nm和40～46nm;随着掺杂浓度增大,π偏振吸收系数呈现饱和趋势,且荧光峰的位置出现了红移.此外,还采用Nd:YAG激光器测试了晶体的激光损伤阈值,实验表明,随着Yb3+掺杂浓度从4.1at%增加到22.9at%,激光损伤阈值也相应地从19.9×109W/cm2逐渐减小到2.79×109W/cm2.

In this paper, the non-doped and Yb3+-doped GdV04 single crystals grown by the Czochralski method are described. The non-doped GdV04 crystal has high transmittance, about 81%, from 400nm to 3000nm. The polarization absorption spectra and the non-polarization fluorescence spectra of Yb: GdVO4 crystals at the room temperature show that GdV04 crystals with different Yb 3+ -doped concentration are the laser crystals with large absorption bands and the emission bands of which the FWHM are about 44-52nm and 40-46nm respectively. With the Yb 3+-doped concentration increasing, the π-polarization absorption coefficients of Yb:GdVO4 crystals tend to be saturated. The laser damage thresholds of YbGdV04 crystals were also determined by using Nd:YAG laser. The results indicate that the laser damage threshold decreases from 19.9 ×109W/cm2 to 2.79 × 109W/cm2 as the Yb3+ -doped concentration increases from 4. 1at% to 22.9at% .