[2] K. Miazato, D. F. Sousa, A. Delben et al.. Upconversion mechanisms in Tm3+ doped lead fluoroindogallate glasses[J]. J. Non-Cryst. Solids, 2000, 273(1-3): 246～251

[3] Shiqing Xu, Zhongmin Yang, Junjie Zhang et al.. Upconversion fluorescence spectroscopy of Er3+/Yb3+-codoped lead oxyfluorosilicate glass[J]. Chem. Phys. Lett., 2004, 385(3～4): 263～267

[5] Shiqing Xu, Zhongmin Yang, Guonian Wang et al.. Upconversion fluorescence spectroscopy of Er3+-doped lead oxyfluorosilicate glass[J]. Chin. Opt. Lett., 2003, 1(9): 544～546

[6] N. Rakov, G. S. Maciel, M. L. Sundheimer et al.. Blue upconversion enhancement by a factor of 200 in Tm3+-doped tellurite glass by codoping with Nd3+ ions[J]. J. Appl. Phys., 2002, 92(10): 6337～6339

[7] Shiqing Xu, Zhongmin Yang, Guonian Wang et al.. Effects of chloride introduction on upconversion luminescence in Tm3+ doped tellurite glasses[J]. Spectrochimica Acta Part A, 2004, 60(13): 3025～3028

[8] Jianhu Yang, Nengli Dai, Shixun Dai et al.. Enhancement of uipconversion luminescence in Er3+ doped tellurite glasses due to the introduction of PbCl2[J]. Chem. Phys. Lett., 20003, 376(5-6): 671～675

[10] Shiqing Xu, Hongtao Sun, Shixun Dai et al.. Upconversion luminescence of Tm3+/Yb3+-codoped oxyhalide tellurite glasses[J]. Silid State Communications, 2005, 133: 89～92

[12] P. M. Peters, S. N. Houde-Walter. Local structure of Er3+ in multicomponent glasses[J]. J. Non-Cryst Solids, 1998, 239(1～3): 162～169