Er3+:YAlO3 upconversion laser

Upconversion lasing in Er:YAlO₃ is reported. Laser emission was produced using both sequential two-step pumping and cross-relaxation energy transfer. In addition, photon avalanche upconversion pumping was demonstrated. Selection among these pumping mechanisms is determined by the pump wavelength, and laser operation was obtained with excitation between 785 nm and 840 nm. The highest laser output power was achieved at 34°K, where 918 mW of pump power at 807 nm produced 121 mW of TEM₀₀ emission. The optical conversion efficiency was 13%. Repetitively Q-switched operation is reported, and the temporal- and temperature-dependence of the laser output is discussed     

多波长Er3+:YAlO3激光的偏振特性

本文从实验上研究了掺杂10at%Er3+离子a轴Er3+YAlO3（Er:YAP）激光器同时起振的2.7110μm,2.7299μm和2.7950μm三条谱线的偏振特性,发现2.7110μm和2.7950μm激光为线偏振光,其偏振方向平行结晶的b轴方向.2.7299μm激光为部分偏振光,椭圆的长轴沿结晶的c轴方向.文中给出了三者的输出特性.     

Er3+-Yb3+ and Er3+ doped fiberlasers

Single-mode fiber lasers operating at ~1.57 μm are described. Output powers of >2 mW are reported for laser diode pumped operation. Direct comparison is made between fiber lasers using sensitized erbium (Er³⁺ and Yb³⁺) and erbium on its own. The performance of Er³⁺-Yb³⁺ fiber lasers is analyzed in more detail as a function of fiber length. Both CW and Q-switched operations are studied and the results obtained demonstrate that practical sources at 1.5 μm are available from diode pumped Er³⁺ -Yb³⁺ systems     

YAlO3∶Eu3+发光纳米纤维的制备与表征

采用静电纺丝技术制备了聚乙烯吡咯烷酮PVP/[Y(NO3)3+Al(NO3)3+Eu(NO3)3]复合纤维,将其进行热处理,得到了YAlO3:Eu3+发光纳米纤维。采用X射线衍射(XRD)、扫描电镜(SEM)、荧光光谱等技术对样品进行了表征。PVP/[Y(NO3)3+Al(NO3)3+Eu(NO3)3]复合纤维经1200℃焙烧2h后,获得了YAlO3:Eu3+纳米纤维,属于正交晶系,空间群为Pnma。用Shapiro-Wilk方法检验了纤维直径分布情况,在95%的置信度下,纤维直径属于正态分布。PVP/[Y(NO3)3+Al(NO3)3+Eu(NO3)3]复合纤维表面光滑,纤维分散性较好,有很好的长径比,尺寸均一,平均直径为(152.9±26.0)nm;YAlO3:Eu3+纳米纤维的平均直径为(106.7±20.2)nm。在234nm的紫外光激发下,YAlO3:Eu3+纳米纤维的主要发射峰位于590nm和609nm处,分别属于Eu3+的5 D0→7F1跃迁和5 D0→7F2跃迁,Eu3+掺杂离子浓度对YAlO3:Eu3+发射峰的峰型与位置均没有影响,当Eu3+掺杂离子浓度为5%时,YAlO3:Eu3+纳米纤维发光最强。     

YP_5O_(14):Er~(3+),Tm~(3+)晶体的合成

研究了水热法合成晶体,浓度配比、生长温度对晶体生长习性的影响.合成了一系列化学计量比的Y_(1-x-0.3)Er_(0.3)Tm_xP_5O_(14)(x=0.01～0.1)晶体,观察和分析了晶体的缺陷及成因,测定和讨论了晶体结构.     

Ag纳米颗粒对Er3+/Tm3+/Yb3+共掺铋锗酸盐玻璃上转换发光特性的影响

采用传统熔融淬冷法制备了系列Er³⁺/Tm 3+/Yb³⁺共掺复合Ag纳米颗粒的铋锗酸盐玻璃样品。从吸收光谱中 确定了Ag纳米颗粒表面等离子体共振(SPR)峰位于545nm附近;透射 电镜(TEM)图像中观察到均匀分布的Ag纳米颗粒,尺寸 约为6～18nm。研究了纳米Ag含量对Er3＋/Tm3＋ 共掺复合Ag纳米颗粒铋锗酸盐玻璃上转换发光特性的影响,结果表 明,Tm³⁺离子472nm处的上转换蓝光、Er³⁺离子525nm处的上转换绿光、543nm处的上转换 绿光和661nm处的上转换红光发光强度在AgCl含量的质量百分数为 1%时达到最大值,与未掺杂AgCl的基质玻璃相比,分别提高了约3.2、3.8、5.4倍。     

Ag纳米颗粒对Er3+/Yb3+共掺铋锗酸盐玻璃上转换发光性能的影响

采用熔融退火法制备了Er³⁺/Yb³⁺共 掺复合银(Ag)纳米颗粒的铋锗酸盐玻璃,对玻璃样品 进行物理性质、透射电镜(TEM)图像和光谱性能测试,分析了铋锗酸盐玻璃样品中Er³⁺的上转换 发光机理。研究表明:随着退火温度的增加,Ag纳米颗粒不断析出,绿光(527nm波长 )和红光(661nm波长)发光强度都得到了较大增强,在420℃时,上转换发光强度分别为未掺 杂AgCl时的4.45和4.22倍。其上转换发光增强的原因归结于Ag 纳米颗粒表面等离子体共振(SPR)导致局域场电场增强和Ag⁰→Er³⁺的能量转移。     

LD泵浦Er3+: Yb3+共掺全固态激光器设计

对LD泵浦Er3+:Yb3+共掺全固态激光器进行了整体设计,利用矩阵光学方法推导了高斯光束经耦合系统聚焦后束腰宽度和像距的计算公式。考虑激光棒的热透镜效应,对有源平平腔、平凹腔进行了数值计算,分析了谐振腔的稳定性。最后,根据激光谐振条件,确定了激光输出镜及滤光片的镀膜方案,为最终获得高效率、稳定的激光输出提供了理论依据。     

中频溅射技术制备镱铒共掺Al2O3光波导

在硅单晶(100)衬底上用热氧化法氧化一层SiO₂做缓冲层,在高纯铝靶上镶嵌金属Yb,Er,然后用中频磁控溅射法制备了镱铒共掺杂氧化铝薄膜。讨论了靶电压及沉积速率随氧流量的变化的磁滞回线效应,分析得出了沉积氧化物薄膜的最佳氧流量。在室温下检测到了薄膜的位于1535nm的很强的光致发光光谱(PL),并在光学掩模下用BCl₃离子束对薄膜样品进行刻蚀,得到条形光波导。     

Anomalous dispersion in Er3+ and Yb3+-dopedfibers

In experimental and theoretical study of anomalous dispersion in Er³⁺and Er³⁺-Yb³⁺-doped fibers has been developed. Anomalous time delay caused by both absorption and emission at 1.535 μm has been theoretically calculated and experimentally measured. A pump power dependence of anomalous time delay in rare-earth-doped fibers has been theoretically calculated and experimentally investigated. It has been shown that pump power fluctuations lead to propagation time jitter in Er³⁺-doped fiber amplifiers. The pulse interaction due to refractive index change caused by gain saturation is predicted. It has been shown that for Er ³⁺-doped fibers with SiO₂-GeO₂ core composition, the anomalous dispersion per 1-dB gain is twice that of fibers with SiO₂-Al₂O₃ core, which is caused by gain curve form difference. A scheme of mutual compensation of intrinsic fiber dispersion and anomalous dispersion caused by Er³⁺ in the region 1.532-1.537 μm has been suggested     

Er3+/Yb3+双掺光纤放大器理论模型

本文在分析一些文献的基础上,仿照掺Er3+光纤放大器的理论模型,尝试建立了一个Er3+/Yb3+双掺光纤放大器的理论模型。利用本模型,可以模拟双掺光纤中信号、泵浦及放大的自发辐射(ASE)的变化情形,并得到一些有意义的数值结果。     

Spectroscopic Properties and Laser Performance of Er3+ and Yb3+ Co-Doped GdAl3(BO3)4 Crystal

An Er:Yb:GdAl₃(BO₃)₄ crystal was grown and room-temperature polarized absorption, emission, and gain spectra were investigated. Fluorescence decay curves of Er³⁺ at 1530 nm and Yb³⁺ at 1040 nm in the crystal were measured. Efficient laser operation of Er:Yb:GdAl₃(BO₃)₄ crystal at 1.5-1.6 mum was realized. Quasi-continuous-wave output powers of 1.8 W with slope efficiency of 19% and 0.78 W with slope efficiency of 14% were achieved in diode-pumped c-cut and c-cut and a-cut crystals, respectively. The output spectrum and polarization of Er:Yb:GdAl₃(BO₃)₄ laser were also investigated.     

Er3+,Yb3+:glass/Co2+:MgAl2O4复合材料LD泵浦被动调Q微型激光器

报道了一种应用于激光测距的Er³⁺,Yb³⁺:glass/Co²⁺:MgAl₂O₄复合材料LD泵浦的被动调Q微型激光器。 采用玻璃与晶体复合技术,将增益介质Er3＋/Yb3＋共掺 磷酸盐玻璃和被动调Q可饱和 Co²⁺:MgAl₂O₄晶体进行了光学热复合,复合材料会降低增益介质内部的温度梯度 ,使热焦距变长,模体积 增加,激光光束质量提高;另外,复合材料使腔内损耗减小,腔内的粒子数密度提高,脉宽 变窄,输出能 量增加,从而激光器性能得到提高。在重复频率为10Hz情况下,采 用中心波长为940nm的单管LD作为泵 浦源,获得单脉冲能量为210μJ、脉冲宽度为2.8ns,峰值功率大于70kW的波长为1.5 μm的被动调Q激光输出,光束质量为1.2     

Diode-array pumping of Er3+/Yb3+ Co-dopedfiber lasers and amplifiers

Single-mode double-clad Er³⁺/Yb³⁺ co-doped fibers are shown to be suitable for diode array pumping at around 960 nm. A fiber laser with 96-W output power at 1.53 μm and a power amplifier exhibiting a small signal gain of 24 dB and a saturated output power of +17 dBm are reported     

LD泵浦的kHz,Er3+,Yb3+:glass被动调Q微片激光器

目前1.5m LD泵浦铒玻璃被动调Q微型激光器是军事激光测距的研究热点,获得较高的激光重复频率和单脉冲能量尤为重要。文中主要报道了一种应用于激光测距领域的铒镱共掺磷酸盐玻璃被动调Q微片激光器。激光器采用中心波长为940 nm的单管二极管为泵浦源,铒镱共掺磷酸盐玻璃（Er3+,Yb3+:glass）作为增益介质,CO2+:MgAl2O4（CO:MALO）作为可饱和吸收体。通过分析泵浦光斑半径对模式匹配影响,优化泵浦光斑半径,实验分析可饱和吸收体初始透过率T0和输出镜反射率R对输出激光参数影响,优化T0和R值。最终实验中采用增益预泵浦方式,实现重频1 kHz,单脉冲能量40 J,脉宽5.09 ns,峰值功率7.85 kW,光束质量M2=1.4,波长1 535 nm的稳定激光输出。     

Laser action from Ho3+, Er3+, and Tm3+in YAlO3

Laser action has been observed for the following rare-earth ions in YAlO3:Ho³⁺(sensitized with Er³⁺and Tm³⁺), Er³⁺, and Tm³⁺(sensitized with Er³⁺) at wavelengths of 2.123, 0.851, and 1.861 μm, respectively. Measurements of spectroscopic properties, fluorescence kinetics, and laser performance of these ions in YAlO3are reported.     

3 μm laser performance of Ho:YAlO3 andNd,Ho:YAlO3

A study of the 3-μm laser transitions in Ho:YAlO₃ and Nd,Ho:YAlO₃ using both flashlamp and laser pumping is discussed. Fluorescence measurements for the Nd,Ho:YAlO₃ rod indicate that the neodymium is effective in quenching the lower holmium laser level and in sensitizing the upper level. Intracavity laser pumping of Ho:YAlO₃ produced laser lines at 2.92 and 2.85 μm and demonstrated high efficiency     

Er3+ –Y3+-Codoped Al 2O3 for High-Temperature Sensing

Optical high-temperature sensing using the fluorescence intensity ratio (FIR) technique of green up-conversion emissions at 523 and 546 nm in Er³⁺-Y³⁺-codoped Al₂O₃ was studied in a wide temperature range of 295 K-973 K. The maximum sensitivity and the temperature resolution derived from the FIR technique are approximately 0.0035 K^-1 and 0.3 K, respectively, which indicated that Er³⁺-Y³⁺-codoped Al₂O₃ plays an important role for applications in the optical high-temperature sensing.     

Temperature dependence of pulsed laser threshold in YAG:Er3+, Tm3+, Ho +

The variation of pulsed laser threshold with temperature is graphically presented for YAG: Er³⁺, Tm³⁺, Ho³⁺over the range from 90 to 300°K. The active ion is Ho³⁺and threshold for the 2.13-micron line varies between 4 and 60 joules over this temperature range.