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101.
We present the characterization of amplified spontaneous emission (ASE) from newly fabricated Er^3 -doped tellurite fibres.When pumped at 98Ohm,a very broad erbium ASE in the range 1450-1650nm is observed.The changes of ASE with regard to fibre lengths and pumping power were measured.The output of 2mW from an Er^3 -doped tellurite fibre ASE source is obtained with the pump power of 540mW.  相似文献   
102.
采用时域有限差分方法(FDTD)模拟了石英玻璃和掺钕磷酸盐激光玻璃表面三角形微裂纹对入射光调制后的分布。TE模式光波入射,最大调制电场幅值出现在玻璃体内部;TM模式光波入射,最大调制电场幅值则发生在裂纹的缝隙中。两种入射光模式下,后表面的调制电场幅值增大倍数在相同裂纹条件下均比前表面大。TE模式入射时,当入射光在裂纹和玻璃表面相继发生全反射时,得到的调制电场幅值最大;后表面最大调制电场幅值随着裂纹在界面投影长度的增加、开口宽度的变大及裂纹深度的增加而分别增大。  相似文献   
103.
Strong upconversion luminescence of Er3 /Yb3 -doped lead halide tellurite glass under 976nm excitation is demonstrated. Three emission bands centred at 525 nm, 545 nm, and 655 nm resulting from the transitionsfrom the excited states 2H11/2, 4S3/2, and 4F9/2 to the ground state 4I15/2, respectively, are observed evenat 60mW pumping power. The power dependent intensity and the upconversion mechanisms responsible forthe luminescence are evaluated and discussed. The obtained results might provide useful information for thedevelopments of upconversion lasers.  相似文献   
104.
The thermal properties of 68TeO2-15BaF2-5SrF2-10LaF3-2KF glass were measured by different temperature analysis (DTA). Up-conversion luminescence of Er3 ion in the obtained glass was investigated. Mechanism of up-conversion emission was discussed. The result shows that the obtained oxyfluoride tel-lurite glass 68TeO2-15BaF2-5SrF2-10LaF3-2KF has a good thermal stability (△T = 153.6℃) and strong up-conversion green emissions around 527 nm and 549 nm and red emission at 660 nm. This glass can be a promising host material for up-conversion fiber lasers.  相似文献   
105.
We investigate the absorption, stimulated emission cross section and potential laser parameters of Yb^3 doped gernano-silicate glasses (GSY glass). The emission cross section is evaluated by using the measured absorption spectra and the principle of reciprocity. It is found that Yb^3 in GSY glasses has high stimulated emission cross section of 0.5-0.65pm^2 near 1020nm and exists long measured fluorescence lifetime of 1.20-2.00ms. Compared with other glass hosts, the GSY glass exhibits excellent general spectroscopic properties for Yb^3 -doped double-cladding fibres.  相似文献   
106.
掺铒铝硅酸盐玻璃光谱和上转换荧光性质研究   总被引:2,自引:1,他引:1  
利用Judd小Ofelt(J—O)理论和吸收光谱计算了Er^3 、Yb^3 掺杂的铝硅酸盐玻璃的J—O参量、振子强度、跃迁几率、荧光寿命,量子效率以及上转换系数等参量,比较了饵离子^I13/2—^I15/2跃迁的光谱参量的计算与测量值,并讨论了玻璃中OH—浓度与荧光寿命、绿色上转换发光强度与抽运光功率的关系。  相似文献   
107.
Upconversion fluorescence emission of Er3+-doped oxyfluorosilicate glass excited at 975 nm is experimentally investigated. The results reveal that the intense green and red emission, and weak blue emission centered at 525, 543, 655, and 410 nm, respectively. A two-photon upconversion process is assigned to the green and red emission while a three-photon process is responsible for blue upconversion. The possible upconversion mechanisms are discussed based on excited state absorption and energy transfer between excited Er3+ ions. The intense upconversion fluorescence of Er3+-doped lead oxyfluorosilicate glass may be a potentially useful material for developing upconversion optical devices.  相似文献   
108.
Yb3+与其它稀土离子相比有最简单的能级结构,这使它具有一些独特的性质,如避免激发态吸收,消除上转换和浓度猝灭等,因此它是高能输出激光器介质的理想掺杂离子。氟磷玻璃综合了氟化物玻璃和磷酸盐玻璃的优点,可降低磷酸盐的声子能量,改善其易吸湿性;提高氟化物玻璃的物理化学性能等,这使它成为稀土掺杂可调谐光纤激光器的很好的掺杂介质。众多研究表明,Yb3+掺杂氟磷玻璃是一种很有前途的激光工作物质。本文总结了Yb3+掺杂氟磷玻璃的特点,性质,结构及存在的问题。  相似文献   
109.
 采用时域有限差分方法(FDTD)模拟了石英玻璃和掺钕磷酸盐激光玻璃表面三角形微裂纹对入射光调制后的分布。TE模式光波入射,最大调制电场幅值出现在玻璃体内部;TM模式光波入射,最大调制电场幅值则发生在裂纹的缝隙中。两种入射光模式下,后表面的调制电场幅值增大倍数在相同裂纹条件下均比前表面大。TE模式入射时,当入射光在裂纹和玻璃表面相继发生全反射时,得到的调制电场幅值最大;后表面最大调制电场幅值随着裂纹在界面投影长度的增加、开口宽度的变大及裂纹深度的增加而分别增大。  相似文献   
110.
Nd3+ strengthens the Er3+:2.7-μm emission 104 times in fluorophosphate glass;in addition,it can also decrease its upconversion effects and the 1.5-μm emission accordingly.Cross-relaxation process is the principal transition mechanism in this codoping system.Compared with Er3+ singly doped glass,JO parameters along with the Arad,β,τR values of Er3+ change markedly in Er3+:Nd3+ codoped glass because Nd3+ greatly in?uences the local environment around Er3+.Results also show that Nd3+ has a good 4I13/2 lifetime quenching effect as well as thermal load reduction ability for Er3+:2.7-μm emission.  相似文献   
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