UV-Blue Upconverted Emission from Nd^3＋-Doped InF3-Based Heavy-Metal Fluoride Glasses for Blue Upconversion Fibre Laser

We report spectral properties and thermal stability of Nd^3 -doped InF3-based heavy-metal fluoride glasses. Fluoroindate glasses in the chemical compositions (in mol％) of (38-x)InF3-16BaF2-20ZnF2-20SrF2-3GdF3-1GaF3-2NaF-xNdF3 (x = 0.1, 0.5, 1, 2, 3) have been prepared under a controlled atmosphere in a dry box. Strong UVblue upconversion emission from a green excitation wavelength has been observed and the involved mechanisms have been explained. Near-infrared emission occurs simultaneously upon excitation of the UV-blue upconversion emissions with a cw Ar^ laser. The upconversion spectra have revealed four dominant emissions at 354, 380, 412 and 449nm, which belong to the transitions of ^4D3/2 → ^4I9/2, 4^D3/2 → ^4I11/2 and ^2P3/2 → ^4I9/2, ^4D3/2 → ^4I13/2 and ^2P3/2 → ^4I11/2, ^4D3/2 → ^4I15/2 and ^2P3/2 → ^4I13/2, respectively.     

Visible Upconversion Emission in Er3＋—Doped GeO2—PbO—PbF2 Glass

The upconversion fluorescence emission of Er3 -doped 60GeO2-2OPbO-2OPbF2 glass was experimentally investigated under the pump of 976-nm laser diode. The results reveal the existence of intense emission bands centred around 524, 545, and 657nm at room temperature. The green emission at 524 and 545nm is due to the 4S3/2 2 Hll/2→ 4I15/2 transition and the red emission of 657nm originates from the 4F9/2-→4I15/2 transition of Er3 . The quadratic dependence of the green and red emissions on excitation power indicates that a two-photonabsorption process occurs under the 976-nm excitation. The excited- state absorption from 4I ll/2 and the cross relaxation between two Er3 ions in the 4I ll/2 state contribute to the green emission. The red emission at 657nm is attributed to the excited-state absorption and cross relaxation processes in the 4I13/2 level as well as the 4S3/2 level nonradiative transition of Er3 .     

Blue Upconversion Luminescence in Tm^3＋／Yb^3＋-Codoped Lead Chloride Tellurite Glass

The upconversion properties of Tm^3 /Yb3 -codoped lead chloride tellurite glass under 980hm excitation were investigated. The intense blue (476nm) emission and weak red (649 nm) emission corresponding to the ^1G4→4 ^3H6 and ^1G4→^3H4 transitions of Tm^3 ions, respectively, were simultaneously observed at room temperature. The dependence of upconversion intensities on excitation power and the possible upconversion mechanisms are evaluated. The intense blue upconversion luminescence of Tm^3 /Yb^3 -codoped lead chloride tellurite glass can be used as potential host material for the development of blue upconversion optical devices.     

Optical transitions in Er^3＋ doped lead germanate glasses

Er^{3+}- and Er^{3+}/Yb^{3+}-doped lead germanate glasses that are suitable for use in fibre lasers and optical amplifiers as well as optical waveguide devices have been fabricated and characterized. The absorption spectra from near-infrared to visible were obtained and the Judd－Ofelt parameters were determined from the absorption band. Intense and broad 1.53μm infrared fluorescence and visible upconversion luminescence were observed under 976 nm diode laser excitation. For 1.53μm emission band, the full widths at half-maximum are 36, 37, 51 nm for GPE, GPYE and GPFE samples, respectively. For frequency upconversion emission, the intense bands centred at around 524, 545, 657nm are due to the {}^4S_{3/2}+{}^2H_{11/2}→{}^4I_{15/2} and {}^4F_{9/2}→{}^4I_{15/2} transitions of Er^{3+} ions. The quadratic dependence of the green and red emissions on excitation power indicates that the two-photon absorption process occurs under the 976nm excitation.     

Tm^3＋-doped Ga2O3-GeO2-Bi2O3-PbO（PbF2） Glasses for 1.47-μm Optical Amplifications

We report the spectroscopic properties and thermal stability of Tm^3＋-doped Ga2O3-GeO2-Bi2O3-PbO（PbF2） glasses for 1.47-μm optical amplifications. Effects of PbF2 doping on the optical properties and thermal stability of Tm^3＋ -doped gallate-germanium-bismuth-lead glass are inestigated. The measured peak wavelength and full width at half-maximum of the fluorescence are 1465nm and - 120 nm, respectively： Siguificant enhancement of the 1.47-μm emission and the lifetime of a a^3H4 level with increasing PbF2 doping have been observed. The presence of GeO2 provides two potentials of increasing the thermal stability and shortening the ultraviolet cutoff band of host glasses.     

Yb3+敏化Tm3+掺杂氧卤碲酸盐玻璃的上转换发光研究

研究了Yb2O3浓度对Tm3 /Yb3 共掺氧卤碲酸盐玻璃的上转换发光的影响,分析了上转换发光机理。结果发现,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(475 nm)和微弱的红光(649 nm),分别是由于Tm3 离子1G4→3H6和1G4→3F4跃迁产生的;上转换机理分析表明,上转换蓝光和红光都是由于双光子吸收过程。随Yb2O3浓度增加,Yb3 离子寿命降低,Yb3 到Tm3 的能量转移效率增加,上转换蓝光和红光强度先增加,在Yb2O3摩尔比为3时达到最大,然后降低。分析认为,Yb3 的浓度猝灭主要是由于3H4(Tm3 )→2F5/2(Yb3 )反向能量转移的结果。结果表明Yb3 敏化Tm3 掺杂氧卤碲酸盐玻璃是一种上转换蓝光激光器的潜在基质材料。     

凝胶基质高效可调谐固态染料激光器

采用溶胶－凝胶工艺制成激光染料掺杂有机改性凝胶玻璃。用室温下调ＱＮｄ：ＹＡＧ激光器倍频光泵浦凝 胶基,成功地获得了高转换效率,长寿命,可调谐固态染料激光器的激光输出。其中ＳｉＯ２－Ｏｒｍｏｓｉｌ基质Ｐｙｒｒｏｍｅｔｈｅｎｅ５９７染料激光器,激光输出阈值低于１０μＪ,斜率效率η＝６１％,５５０－５９４ｎｍ波长范围内连续可调谐,激光输出能量下降１０％所承受的激光脉冲数大于２．５＊１０＾４个（激光泵浦频     

Cr3+,Yb3+,Er3+共掺磷酸盐铒玻璃转镜调Q激光性质研究

研究了Cr³⁺,Yb³⁺,Er³⁺共掺磷酸盐铒玻 璃转镜调Q激光性质.三种Er₂O₃掺杂浓度的激光实验结果表明，在Er₂O₃名义掺杂浓 度为0.5wt％时，玻璃的综合激 光性质最好，重复频率为0.1Hz时，它的激光阈值功率为14.5mJ，最大输出能量为9.6mJ ，斜率效率为0.55％.在同种实验条件下，比较了Cr14和Kigre公司生产的QE-7S激光性质参数，实验表明，前者激光阈值功率稍低，而后者的斜率效率和最大输出功率略高. 关键词： 3+-Yb³⁺-Er³⁺共掺')" href="#">Cr³⁺-Yb³⁺-Er³⁺共掺 磷酸 盐玻璃 光谱性质 激光性质     

玻璃掺杂量子点的倍频效应产生的理论研究

应用统计理论和量子力学理论对量子点掺杂的倍频效应产生的机制与量子点倍频光的电极化率与量子点的尺寸大小的关系进行了理论研究，结果较好地解释了实验所观察到的规律。     

铝硅玻璃中Fe~(3+)、Cr~(3+)的EPR研究

本文用EPR技术研究了含Fe~(3+)和Cr~(3+)离子的铝硅破璃的结构性质,从理论上分析了实验结果.并且用含有Fe~(3+)离子的多晶样品——莫来石的玻璃样品进行了实验比较,最终认为铝硅玻璃和莫来石中的Fe~(3+)离子附近的局部环境类似.