| The 21 st century is the era of optical communication, high-speed, high-capacity optical communications networks has become a new research target. The invention of wavelength-division multiplexing (WDM) and the Erbium-doped fiber amplifier (EDFA), which is invented in 21st nineties, make the transmission of information in long distance and great capacity possible. Conventional Erbium-doped fiber amplifiers is silica-based, which work in the C-band (1530nm-1565nm). However, with the further development of the internet, they cannot meet the requirement of the system any more. New generation fiber communication system has been paid more attention to light amplification in the S-band (1450nm-1520nm). But it is impractical to achieve the optical amplification in this Band by EDFA. Consequently, investigating other rare earth ions'luminescence properties to develop the new S-Band fiber amplifier is becoming increasing important.Nowadays, most fibers are silica-based. Compared with the silica-based materieals, telluride materieals are more stable; more corrosion-resistant; and have higher ions solution. However, there is little research in this field. In this paper, Tm-doped telluride materieals and codoped Tm with other rare earth ions materieals are prepared. The luminescence properties of Tm ions in the codoped Tm with other rare earth ions materieals are got by experiment, and the theoretical analysis is taken. Tm/Yb codoped fiber is prepared; optial properties of the fiber are analyzed. Moreover, a fiber amplifier, which in cavity resonator form, is set up. This work has laid a solid foundation for the future research of high performance Tm doped fiber laser and fiber amplifier. In this work, Tm/Yb co-doped material show its good potential in blue laser, the laser performance of Tm/Yb co-doped material also been investigated. Main works of the paper are summarized as follows:(1) Tm-doped telluride glass and codoped Tm with other rare earth ions telluride glass are prepared; Tm/Yb codoped telluride fiber is prepared. That is the foundation of properties test of Tm in codoped Tm with other rare earth ions telluride glass.(2) The luminescence properties of the telluride materials have been investigated. 808nm and 980nm diode laser are used as pumping source, respectively. Under the laser pumping, the luminescence spectrums of the telluride materials in different codoped ions are record.890nm fluorescence is the first time found in Tm/Yb co-doped material, and 1370nm fluorescence is also found in Tm/Yb co-doped material with the dispearence of 1470nm fluorescence, which is the characteristic fluorescence of Tm ion. The resulting spectrums are analyzed. Obvious blue light is generated in Tm/Yb codoped glass and upper level energy conversion is confirmed.(3) Using J-0 theory theoretically analyzed the optical properties of Tm-doped telluride materieals and Tm/Yb co-doped telluride materieals. The optiacl parameters of Tm/Yb co-doped telluride glass have been got for the first time. The fluorescence performance of Tm/Yb co-doped telluride glass has been explained through the theoretical calculation. The calculation indicates the ratio of Yb in materieal is very important. This conclusion is very important to achieve S-band amplification.(4) The properties of Tm/Yb co-doped telluride fibers have been investigated. Approaches are suggested for solving frailty of telluride-based fibers and difficulty of splicing with conventional silica-based fibers. Besides, the placement and connection of telluride-based fibers is investigated. A fiber amplifier, which in cavity resonator form is set up. The experiment of S-band fiber amplifier is taken.(5) The laser properties of Tm/Yb co-doped telluride materieals have been investigated. The experiment indicates the Tm/Yb co-doped crystal could be a good laser materieal in blue color and inl.5-2^,m eye safe laser. The Tm,Yb:KLu(WO4)2 crystal is growing.The main innovations of this dissertation are as follows: 1. Tm-doped telluride glass and codoped Tm with other rare earth ions telluride glass are prepared; Tm/Yb codoped telluride fiber is prepared. Properties of Tm in codoped Tm with other rare earth ions telluride materials are investigated.2. For the first time,890nm fluorescence and 1370nm fluorescence are found obviously in Tm/Yb co-doped materials. Furthermore, with the appearance of 1370nm fluorescence, the 1470nm fluorescence, which is the characteristic fluorescence of Tm ion, is dispeared. The reasons of these phenomenons are analyzed based on Tm, Yb energy structure.3. For the first time, the optiacl parameters of Tm ions in Tm/Yb co-doped telluride glass are calculated. The calculation indicate the Yb ions in Tm/Yb co-doped glass affect the energy structure of Tm ions, this is confirmed with the new fluorescence appeared and the characteristic fluorescence of Tm ion disappeared.4. For the first time, it is found the fluorescence properties of Tm in Tm/Yb codoped telluride materieals will change with the Tm, Yb ratio diffenence, and this phenomenon is analyzed.5. Tm/Yb codoped telluride fiber is prepared. A fiber amplifier, which in cavity resonator form, is set up. The experiment of S-band fiber amplifier is taken.6.480nm blue up-convertion fluorescence is recored in fluorescence test on Tm/Yb co-doped material. For the first time, Tm,Yb:KLu(WO4)2 crystal is choscen as the blue laser material, and the Tm, Yb:KLu(WO4)2 crystal is under growing.
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