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61.
Up-convertion(UC)perovskite Er3+-doped Pb TiO3(Er-PTO)nanoparticles with green and red emissions were synthesized via the hydrothermal method.The UC properties were manipulated by adjusting the concentration of Er3+ ions dopant.The green emission intensity was decreased as the doping concentration increased from 1% to 4%(mole fraction),whereas the red emission intensity was increased.The influences of Er3+ ions on the temperature-sensing performance were further investigated.The results demonstrated that Er-PTO nanoparticles with doping 1% Er3+ ions possessed a sensitivity of3.1×10-3 K-1 at 475 K,presenting a high potential in optical heating devices.  相似文献   
62.
Spectral characteristics of the amplified spontaneous emission (ASE) from a novel single mode Er~(3+) doped tellurite fiber with D-type cladding is reported in this letter. When pumped at 980 nm, an ASE source that has nearly a 100-nm flat FWHM bandwidth is obtained with a fiber length of 30-60 cm. Variation of ASE spectra with pump powers and fiber lengths are measured. Output power up to 2.0 mW is obtained with a launched pump power of 660 mW.  相似文献   
63.
Broadband near-infrared emission from transparent Ni^2+-doped sodium aluminosilicate glass-ceramics is observed. The broad emission is centred at 1290nm and covers the whole telecommunication wavelength region (1100- 1700hm) with full width at half maximum of about 340hm. The observed infrared emission could be attributed to the 3T2(F) → 3A2(F) transition of octahedral Ni^2+ ions that occupy high-field sites in nanocrystals. The product of the lifetime and the stimulated emission cross section is 2.15 × 10^-24 cm^2s. It is suggested that Ni^2+- doped sodium aluminosilicate glass ceramics have potential applications in tunable broadband light sources and broadband amplifiers.  相似文献   
64.
测试了不同掺杂浓度和不同厚度下Yb3+ 磷酸盐玻璃的吸收光谱、荧光光谱和荧光寿命 ,计算了积分吸收截面、吸收截面、受激发射截面、自发辐射寿命以及荧光有效线宽等光谱参数 ,讨论了荧光俘获效应对Yb3+ 磷酸盐玻璃光谱性质的影响 .结果表明荧光俘获效应随样品厚度和掺杂浓度的增加而增大 .由于荧光俘获效应的存在使得测量的Yb3+ 磷酸盐玻璃荧光寿命明显长于计算的荧光寿命 ,在 0 2mol%Yb2 O3低掺杂浓度下采用不同厚度 ( <4mm)的样品测量的荧光寿命之间误差为 3 0 %左右 ,高浓度 ( 6mol%Yb2 O3)掺杂下误差可达 43 % .荧光俘获还造成荧光谱线加宽 ,导致荧光有效线宽在低浓度 ( 0 2mol%Yb2 O3)时增加 14% ,在高掺杂浓度 ( 6mol%Yb2 O3)下增加 3 0 %以上  相似文献   
65.
采用高温熔融法和热处理工艺制作了含有GdF3纳米晶的氧氟微晶玻璃。在386 nm激发下,Dy3+掺杂氧氟微晶玻璃的发光强度明显增强,且蓝光对黄光的发光强度比逐渐增大,表明Dy3+已进入到GdF3纳米晶中。在980 nm激光器泵浦下,Er3+,Yb3+共掺氧氟微晶玻璃的上转换发光随着热处理温度的升高明显增强,Er3+的上转换发光出现明显的Stark分裂现象,这亦说明Er3+已进入到GdF3纳米晶相中。通过研究上转换发光强度与泵浦功率的关系,确定绿光上转换发光为双光子过程。  相似文献   
66.
制备了Tm^3+/Yb^3+共掺氧氯碲酸盐玻璃, 研究了玻璃的热稳定性能、 Raman光谱和上转换发光光谱, 分析了上转换发光机制. 结果表明: 通过980 nm的激光二极管激发, 在室温下同时观察到强烈的蓝光(476 nm)和微弱的红光(649 nm), 分别是Tm^3+离子的1G4→3H6和1G4→3H4跃迁. 随氯化铅含量增加, 基质玻璃的热稳定性能增强, 基质玻璃的声子能量降低, 上转换蓝光和红光的强度增加. 表明Tm^3+/Yb^3+共掺氧氯碲酸盐玻璃是一种上转换蓝光激光器的潜在基质材料.  相似文献   
67.
Nd3+-doped tellurite glass and a single mode tellurite glass fiber with a core diameter of 8 μm were prepared in this work. The 1.33-μm emission from the 4F3/2→4I13/2 transition of Nd3+ with a spectral bandwidth of 55 nm in tellurite glass fiber is observed.The lifetime of 164μs of 4F3/2 level and quantum efficiency of about 100 % are obtained.  相似文献   
68.
Erbium-doped glass showing the wider 1.5-/μm emission band is reported in a novel oxide system TeO2-WO3-Nb2O5 and their thermal stability and optical properties such as absorption,emission spectra,cross-sections and fluorescence lifetime were investigated.Compared with other glass hosts,the gain bandwidthproperties of Er3+ in TWN glass is close to that of bismuth glasses,and larger than those of tellurite,germanatc,silicate and phosphate glasses.The broad and flat 4I13/2 → 4I15/2 emission and the largestimulated emission cross-section of Er3+ ions around 1.5 μm can be used as host material for potentialbroadband optical amplifier in the wavelength-division-multiplexing(WDM)network system.  相似文献   
69.
采用油酸辅助的水热法制备了Er3+/Yb3+共掺NaYF4微晶,通过在反应体系中引入Zr4+离子,实现了NaYF4微晶的晶相控制和上转换发光增强。X-射线衍射和扫描电镜结果表明:Zr4+离子的引入能够明显加快立方相α-NaYF4向六方相β-NaYF4的相转变过程。当Zr4+离子的引入摩尔分数为5%时,获得了纯的六方相β-NaYF4微晶。Er3+/Yb3+共掺NaYF4微晶在980 nm激光泵浦下,观察到强的上转换绿光和红光发射,且上转换发光强度随着Zr4+离子添加量的增加逐渐增大。  相似文献   
70.
制备了Ti4+掺杂硼硅酸盐玻璃,根据玻璃样品的差热分析(DTA)进行微晶化处理,测试了Ti4+掺杂硼硅酸盐微晶玻璃的X射线衍射(XRD)谱、透射电镜(TEM)图像、吸收光谱和发射光谱.根据Scherrer公式计算了BaYF5微晶的平均晶粒尺寸并与TEM图像进行比对.在紫外光激发下,观察到Ti4+掺杂BaYF5硼硅酸盐微...  相似文献   
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