Nd∶KY(WO4)2和Nd∶KG(WO4)2晶体吸收光谱性能分析

通过研究分析钨酸盐晶体Nd∶KY(WO₄)₂和Nd∶KG(WO₄)₂在室温下的吸收光谱，发现这2种晶体具有作为激光晶体的优良特性。根据Judd-Ofelt理论和测试所得的吸收光谱及数据，用VC++编程计算出晶体的谱线强度、振子强度、吸收截面等，拟合得Nd³⁺离子的3个晶场调节参数Ω_λ(λ=2，4，6)的值，并从理论上计算了自发跃迁几率、能级寿命、荧光分支比和积分发射截面。从计算得出的荧光分支比β可以看出，Nd∶KY(WO₄)₂(β_1060nm=0.4380)和Nd∶KG(WO₄)₂(β_1060nm=0.4618)晶体荧光分支比都较大，计算了该晶体的X=Ω₄/Ω₆，并将其X值与其他晶体的X值加以比较，Nd∶KY(WO₄)₂和Nd∶KG(WO₄)₂均易于实现1.06μm激光输出，适合作为LD泵浦的钨酸盐晶体激光器。

Absorption spectrum analysis of Nd:KY(WO4)2 and Nd:KG(WO4)2 crystals

Nd∶KY (WO4)2 and Nd∶KG (WO4)2crystals are proved to be good laser crystals through the analysis of their absorption spectrum at room temperature. According to the absorption spectrum and data derived from Judd-Ofelt theory as well as measured absorption and data obtained from the test,VC++ program was used to calculate the intensity of spectral line,oscillator strength and absorption cross-section of the crystals. Then the values of three crystalfield adjusting parameters Ωλ(λ=2,4,6) of Nd3+ ion were obtained by fitting calculation. The spontaneous transition probability,energy level lifetime,fluorescence branch ratio and integrated emission cross-section were calculated theoretically. The calculated fluorescence branch ratio βindicates that the fluorescence branch ratios of both Nd∶KY (WO4)2 (β1060nm=0.4380) and Nd∶KG(WO4)2(β1060nm=0.4618) crystals are large. At last,X=Ω4/Ω6 of Nd∶KY(WO4)2 and Nd∶KG(WO4)2crystals were calculated and compared with those of other laser crystals. It is concluded that Nd∶KY (WO4)2 and Nd∶KG (WO4)2 crystals can produce 1060 nm laser.