[1] [1] Shen S, Maftaly M, Wilson S J. Thulium-doped tellurite glasses for S-band. Opt. Fiber Commun. Conff (OFC), March 17～22, 2001, Anaheim, California. Paper TuQ6

[2] [2] Wang J S, Vogel E M, Snitzer E. Tellurite glass: A new candidate for fiber devices. Opt. Mater., 1994, 3(4):187～203

[3] [3] Doo Hee Cho, Yong Gyu Choi et al.. Energy transfer from Tm3+∶3F4 to Dy3+∶6H11/2 in oxyfluoride tellurite glasses. Chem. Phys. Lett., 2000, 322(5):263～266

[4] [4] Neindre L L, Jiang S B, Hwang B C et al.. Effect of relative alkali content on absorption linewidth in erbium-doped tellurite glasses. J. Non-Crystalline Solids, 1999, 255(1):97～102

[5] [5] Jayasankar C K, Devi A R. Optical properties of Tm3+ ions in lithium borate glasses. Opt.l Mater., 1996, 5:185～201

[6] [6] Tanabe S, Tamai K, Hirao K et al.. Excited-state absorption mechanisms in red-laser-pumped UV and unconversions in Tm3+-doped fluoroaluminate glass. Phys. Rev. (B), 1993, 47(5):2507～2514

[7] [7] Becker P C, Olsson N A, Simpson J R. Erbium-Doped Fiber Amplifiers Fundamentals and Technology. New York: Academic Press, 1999. 95

[8] [8] Judd B R. Optical absorption intensities in rare earth ions. Phys. Rev., 1962, 127(3):750～761

[9] [9] Ofelt G R. Intensities of crystal spectra of rare earth ions. J. Chem. Phys., 1962, 37(3):511～520

[10] [10] Hirao K, Tamai K, Tanabe S et al.. Frequency upconversion and its new mechanism in Tm3+-doped fluoroaluminate glasses. J. Non-Crystalline Solids, 1993, 160(3):261～267

[11] [11] Hanna D C, Percival R M, Perry I R et al.. Frequency upconversion in Tm- and Yb∶Tm-doped silica fibers. Opt. Commun., 1990, 78(2):187～194

[12] [12] Kim Y S, Cho W Y, Shin Y B et al.. Emission characteristics of Ge-Ga-S glasses doped with Tm3+/Ho3+. J. Non-Crystalline Solids, 1996, 203(1～3):176～181

[13] [13] Spector N, Reisfeld R, Boehm L. Eigenstates and radiative transition probabilities for Tm3+(4f12) in phosphate and tellurite glass. Chem. Phys. Lett., 1977, 49(1):49～53