Sr∶BaF_2晶体电子辐照诱生F型色心及其转型研究

F type Centers and Transformation in BaF 2∶Sr Crystals Irradiated by Electron Beam

测试和分析了Ｓｒ∶ＢａＦ２晶体电子辐照前后以及辐照着色的样品光致转型过程的吸收谱。研究结果表明，能量为１．５ＭｅＶ和１．８ＭｅＶ的电子束对Ｓｒ∶ＢａＦ２晶体的辐照注量达１０１５～１０１６ｃｍ－２时，诱生ＦＨ对、Ｆ心及其与杂质的复合色心。用波长为６３２．８ｎｍ的ＨｅＮｅ激光照射电子辐照着色的样品，可使Ｆ心转型成ＦＡ（Ｓｒ２＋）心；再用钠光（５８９．０，５８９．６ｎｍ）照射，又可将ＦＡ（Ｓｒ２＋）心部分回转成Ｆ心。

Optical absorption spectra of BaF 2∶Sr crystals were studied before and after electron beam irradiation,and the process of F type center transformation were also analyzed based on the study of absorption spectra.The results showed that 1.5 and 1.8MeV electron irradiation at the dose of 10 15 ～10 16 cm -2 induced F H pairs, F centers and other centers perturbed by impurities in BaF 2∶Sr crystals.It is suggested that F centers in the crystal can be transferred into F A(Sr 2+ )centers by He Ne laser (wavelength:632.8nm)excitation,and this process can be reversed by Na light (wavelength:589.0,589.6nm)excitation.