掺Er磷酸盐玻璃中红外发光特性研究

Middle Infrared Luminescence Properties of Er_3 + Doped Phosphate Glass

报道了一种最新型可用于 １．５μｍ光纤通信传输介质的掺 Ｅｒ３＋的磷酸盐玻璃，通过对其吸收谱的测量，可看到在９７０ｎｍ附近有一很强的吸收峰，适合于采用ＬＤ激光泵浦。我们在发射波长为９７０ｎｍ的半导体激光器激发下测量了这种材料的发射谱，观察到在红外波段１５４０ｎｍ处有强发射峰。我们从吸收谱出发拟合出了Ｊ－Ｏ强度参数，进而计算出了Ｅｒ３＋离子各相关跃迁的理论振子强度、实验振子强度及自发辐射系数，从结果可得出理论和实验是相符的。

The amplification of telecommunication signals near 1.5μ m has been successfully demonstrated with Er3+ doped silica fiber. However, silica fiber is unsuitable as component in short length devices because the highest possible Er3 + ion concentration in silica fiber is very low around 100ppm. There are several can- didates for matrix glasses that homogeneously contain rare earth ions. Phosphate glass is one of these candi- dates. In this paper, we reported a kind of Er3 + doped phosphate glass which can be used as transmission and amplification medium in 1. 5μm optical communication. The phosphate glass is composed of (mol %) P2O5 (60 )-Na2CO3 (24) -Al2O3-Er2O3 (0.5) -Yb2O3 (2.0). Firstly, We precisely measured 10-gram strating materials as showed proportion, then put them into a electric-resistance furnace with temperature of 200℃ for two hours. After those unwanted vapor and gases were got rid of, we transported them into a silica- molybdenum-rod furnace with 1 200℃. When the batch was melted enough about a half hour, we quickly poured the melted liquid into a cube-shaped mould with 480℃ temperature, then put mould into electric- resistance furnace with 480℃ for anneal. The resulting glass cube was cut and polished for spectra experiments. We have measured the absorption spectrum of the galss with PERK IN-ELMER Lambda 9 spectrome- ter and observed eight absorption bands. Among the eight absorption bands, the absorption band near 970nm was the strongest. Th emission spectrum under 970nm LD excitation has also been acquired. In this spectrum, only a strong emission near 1 540nm wavelength can be observed. We have obtained the Judd-Ofelt parameters by fitting the absorption spectrum and got the resutls as follows.Ω2=4.29×10-20(cm2); Ω4=1.01×10-20(cm2); Ω=0.75×10-20(cm2).The spontaneous emission probabilities of the relevant transition have been calculated with the obstained Judd-Ofelt parame- ters, so we have a theoretic guide for researching the luminescence phenomenon in the phosphate glass. Lastly, we calculated the absorption and emission cross-section near 1 . 5μm by Fuchtbaure-Ladenburg theory, from the results we know that the glass has a big emission cross-section near 1 .5μm emission.