掺钕镉铝硅酸盐玻璃的Judd-Ofelt理论分析与光谱特性

以掺杂光子晶体光纤为介质的光纤激光器一直受到科研工作者的广泛关注,应用于光子晶体光纤纤芯的掺稀土元素玻璃的制备成为研制掺杂光子晶体光纤的关键问题。利用高温熔融工艺制备钕离子掺杂的40SiO_2-14Al_2O_3-(40-x)CdO-2Li2O-2K2O-2Na_2O-xNd_2O_3(x=0.07,0.14,0.21,0.35,0.42,0.56mol)重金属硅酸盐玻璃系统,测试了其吸收光谱和荧光光谱。采用Judd-Ofelt理论,计算了玻璃样品的强度参数Ωt(t=2,4,6)以及钕离子的自发辐射概率、荧光分支比、荧光辐射寿命等参数。利用测得的荧光光谱计算了钕离子能级跃迁4 F3/2→4 I11/2的受激发射截面及荧光有效线宽。结果表明:当掺Nd_2O_3的摩尔分数为0.42时,制备的镉铝重金属硅酸盐玻璃具有较大的受激发射截面和比较宽的荧光有效线宽,且与相关文献中的钕离子掺杂玻璃相比,具有良好的激光性能和增益性能,有望在研制掺杂光子晶体光纤中得到应用。

Judd-Ofelt Theory Analysis and Spectroscopic Properties of Nd3+-Doped Cadmium Aluminium Silicate Glasses

Photonic crystal fiber laser has been attached great attention by many researches,and preparation of photonic crystal fiber cores becomes the key problem in study of photonic crystal fibers.Nd3+ doped lithium-cadmium heavy-metal silicate glass samples have prepared with the method of high temperature melting,which 40SiO2-14Al2O3-(40-x)CdO-2Li2O-2K2O-2Na2O-xNd2O3 (x=0.07,0.14,0.21,0.35,0.42,0.56 mol) samples have been measured absorption and fluorescence spectra.Applying Judd-Ofelt theory,its intensity parameter Ωt(t=2,4,6),the oscillator strength and spontaneous radiation probability of the Nd3+ ion,fluorescence branching ratio,and the fluorescence lifetime were theoretically calculated.Using fluorescence spectrum,the stimulated emission cross section of the 4F3/2→4I11/2 transition and the full width at half maximum of the fluorescence band were also measured.The result demonstrates that the Nd3+ doped lithium-cadmium heavy-metal silicate glass sample When mixing Nd2O3 mole fraction of is 0.42 possesses a large stimulated emission cross section and a wide fluorescence band compared with the literature of neodymium ions doped glass.These parameters clearly indicate that this kind of silicate glass has a good laser excitation property and is expected to be applied in the study of the doped photonic crystal fibers.