Yb:Y2-2xLa2xO3激光透明陶瓷的光谱性能

It was first reported the spectral properties of a low-temperature sintered transparent Yb: Y2-2x La-2x O-3 laser ceramics. Yb: Y2-2x La-2x O-3 laser ceramics have broad absorption band and large absorption cross- section of 4.0 x 10(-20) cm(2) at wavelengths 977nm of the highest absorption peak. Its fluorescence lifetime is 1.1 ms, and the emission cross-sections are 1.0 x 10(-20) cm(2) and 0.7 x 10(-20) cm(2) at wavelengths 1033nm and 1077nm, respectively. All the optical properties are similar to those of single crystals.

Spectral properties of Ho : GdVO4 single crystal

Absorption and emission spectral properties of GdVO4 single crystal doped with Ho3+ ions were investigated at room temperature. Polarized absorption cross section is calculated in the range of 400-2200nm. Results were analyzed and parameters were calculated based on Judd-Ofelt theory, the emission spectrum shows that the emission intensity around the wavelength of 546 nm associated with transition S-5(2) -> I-5(8) is much stronger than other bands in the observed range and potentially enable the green light output around this emission band in this crystal. (c) 2006 Elsevier B.V. All rights reserved.

Investigation of the spectroscopic properties of Yb3+-doped yttrium lanthanum oxide transparent ceramic

Spectroscopic properties of (Y0.9-xLa0.1Ybx)(2)O-3 transparent ceramic were studied. Two main absorption peaks of the specimen are centered at 940 and 970 nm, which are suitable for InGaAs laser diode pumping. The main emission peaks were located at 1032 and 1075 nm with larger emission cross-section and longer fluorescence lifetime than those of Yb:Y2O3. These properties of (Y0.9-xLa0.1Ybx)(2)O-3 transparent ceramic are favorable to achieve high efficiency and high power laser output. (c) 2007 Elsevier B.V. All rights reserved.

Spectral characterization of transparent (Nd0.01Y0.94La0.05)(2)O-3 laser ceramics

The spectrum properties of transparent (Nd0.01Y0.94La0.05)(2)O-3 ceramics were investigated. It was found that all absorption bands of (Nd0.01Y0.94La0.05)(2)O-3 ceramics are broadened, of which the full width at half maximum of the peak centered at 804 nm is 8 nm and its absorption cross section is 1.02x10(-20) cm(2). The emission cross section of (Nd0.01Y0.94La0.05)(2)O-3 ceramics located at 1078 nm is 5.71x10(-20) cm(2) and its fluorescent lifetime is 0.214 ms, which are similar to those of 1.0 at. %Nd:Y2O3 ceramics. These indicate that (Nd0.01Y0.94La0.05)(2)O-3 transparent ceramics has excellent spectroscopic properties.

Growth and spectral properties of Yb : FAP single crystal

In this paper, single crystal of ytterbium (Yb) doped Ca-5(PO4)(3)F (FAP) has been grown along the c-axis by using the Czochralski method. The segregation coefficients of Yb3+ in the Yb:FAP crystal has been determined by ICP-AES method. The absorption spectrum, fluorescence spectrum and fluorescence lifetime of the Yb:FAP crystal has been also measured at room temperature. In the absorption spectra, there are two absorption bands at 904 and 982 nm, respectively, which are suitable for InGaAs diode laser pumping. The absorption cross-section (sigma(abs)) is 5.117 x 10(-20) cm(2) with an FWHM of 4 nm at 982 nm. The emission cross-section is (sigma(em)) 3.678 x 10(-20) cm(2) at 1042 nm. Favorable values of the absorption cross-section at about 982 nm are promising candidates for laser diode (LD) pumping. (c) 2005 Elsevier B.V. All rights reserved.

Spectroscopic properties of Nd3+:(La,Sr)(Al,Ta)O-3 crystal

A new laser crystal Nd3+:(La, Sr)(Al, Ta)O-3 (abbreviated as Nd3+:LSAT) has been grown by the conventional Czochralski method. The absorption and luminescence spectra of trivalent neodymium in Nd3+:LSAT crystal were measured at room temperature. The value of absorption and emission cross-section was calculated. The Judd-Ofelt analysis was applied to the crystal to get the phenomenological parameters (Omega(i), i = 2,4,6), the line strengths, the radiative transition rates, the branching ratios and the radiative lifetime. (C) 2006 Elsevier B.V. All rights reserved.

Spectroscopic properties of Yb:YAP crystal

The 10at% Yb-YAP crystal has been grown by the Czochralski method. The absorption and emission spectra and fluorescence lifetime of Yb:YAP crystal at room temperature were studied. There is a strong absorption band centered at 959 nm and the absorption cross-section of 1.51 × 10^-20 cm². The emission cross-section at 1040 nm is 0.6 × 10^-20 cm² and the fluorescence lifetime is about 1.2 ms. The effects of O₂-annealing on the spectral properties were studied. The spectroscopic properties strongly depended on the axis direction and b axis was the best direction for laser output. The spectrum parameters of Yb:YAP and Yb:YAG crystal were compared.}

Er^3＋／Yb^3＋共掺的氧化镧钇透明陶瓷的光谱性能研究

采用传统无压烧结工艺制备了Er^3＋／Yb^3＋共掺的氧化镧钇透明陶瓷并对其光谱性能进行了研究．样品具有较大的吸收和发射截面．La2O3的添加使样品的荧光寿命（τs）与玻璃接近，当Yb^3＋和Er^3＋的掺杂量分别为5at％和0．5at％时，测得τs=9．65ms．这种荧光寿命长、发射截面大和线宽窄的特性有利于微型、可集成化和大功率激光输出的实现．

Yb:YAP与Yb:YAG晶体光谱性能比较

应用中频感应提拉法生长出掺杂浓度为10 at.-%的Yb:YAG与Yb:YAP晶体，对比了室温下两种晶体的吸收和发射光谱特性。结果表明，Yb:YAG晶体比Yb:YAP晶体有更好的激光性能和低的阈值；同时对比发现，Yb:YAP晶体的吸收截面是Yb:YAG晶体的2.16倍，它容易实现LD泵；由于Yb:YAP晶体的各向异性，它有轴向效应明显，它可以产生偏振激光。

Nd：YbVO4晶体的拉曼光谱和荧光光谱研究

用群论的方法计算了Nd：YbVO4晶体的拉曼活性振动模数目，在室温下测得了其极化拉曼谱线，并指认了在不同几何配置下，各振动模式所对应的频率。同时，测得了室温下晶体的吸收谱，得到了中心波长为808am吸收峰的半高宽为12nm，并在J-O理论的基础上计算了晶体的光学参数，其三个晶场参数分别为Ω2=6．88945×10^-20cm^2。Ω4=4．13394×10^-20cm^2、Ω6=4．54503×10^-20cm^2，并由此得到^4F3／2能级的荧光寿命为178．69炉，1062nm处的荧光分支比为48．85％，积分发射截面为2．786710^-18cm^2。分别在808nm、940nm激发下测得晶体室温发射谱，观察到了Nd→Yb以及Nd←Yb间的能量传递现象。

Sm:GdVO_4晶体的生长及光谱性能研究

应用中频感应提拉法生长出掺杂浓度为2%原子分数的Sm:GdVO4晶体,研究了室温下c轴方向Sm:GdVO4晶体的吸收和荧光光谱。通过J-O理论计算出强度参数(Ωt),同时计算了对应于4G5/2能级的自发跃迁几率、荧光分支比和辐射寿命。通过荧光光谱计算了对应于566、604和646nm三个发射峰对应的发射截面,结果表明,Sm:GdVO4在604nm的发射截面最大,是掺Sm:YAP在607nm处发射截面的4.4倍。

Fabrication and spectral properties of Nd3+-doped yttrium lanthanum oxide transparent ceramics

Transparent 1 at% Nd3+:Y1.9La0.1O3 ceramics were fabricated with nanopowders prepared by carbonate coprecipitation method. The powder compacts were sintered in H-2 atmosphere at 1550 degrees C for 30 h. The Nd3+:Y1.9La0.1O3 ceramics display uniform grains of about 50 mu m and high transparency. The highest transmittance of the ceramics reaches 67%. The strongest absorption peak is in the wavelength of 820 nm with absorption cross section of 2.48 x 10(-20) cm(2). The absorption is still high at LD wavelength 806 nm with absorption cross section of 1.78 x 10(-20) cm(2) and broad full width at half maximum (FWHM) of about 6.3 nm. The strongest emission peak was centered at 1078 nm with large stimulated emission cross section of 9.63 x 10(-20) cm(2) and broad FWHM of about 7.8 nm. The broad absorption and emission bandwidth of Nd3+:y(1.9)La(0.1)O(3) transparent ceramics are favorable to achieve the miniaturized LD pumping apparatus and ultrashort modelocked pulse laser output, respectively. (c) 2007 Elsevier B.V. All rights reserved.

Growth and spectral properties of Er:Gd2SiO5 crystal

Er3+ -doped Gd2SiO5 (Er:GSO) single crystal with dimensions of circle divide 35 x 40 mm(3) has been grown by the Czochralski method. The absorption and fluorescence spectra of the Er:GSO crystal were measured at room temperature. The spectral parameters were calculated based on Judd-Ofelt theory, and the intensity parameters Omega(2), Omega(4) and Omega 6 are obtained to be 6.168 x 10(-20), 1.878 x 10(-20), and 1.255 x 10(-20) cm(2), respectively. The emission cross-section has been calculated by Fuechtbauer-Ladenbury formula. (c) 2007 Elsevier B.V. All rights reserved.

Intense upconversion and infrared emissions in Er3+;Yb3+ codoped Lu2 Si O5 and (Lu0.5 Gd0.5)2 Si O5 crystals

High optical quality Lu2SiO5 (LSO) and (Lu0.5Gd0.5)(2)SiO5 (LGSO) laser crystals codoped with Er3+ and Yb3+ have been fabricated by the Czochralski method. Intense upconversion (UC) and infrared emission (1543 nm) are observed under excitation of 975 nm. The luminescence processes are explained and the emission efficiencies are quantitatively obtained by measuring the UC efficiency and calculating the emission cross section. The temperature-dependent optical properties of the crystals are also investigated. Our study indicates that Er3+-Yb3+ : LSO and Er3+-Yb3+: LGSO crystals are promising gain media for developing the solid-state 1.5 mu m optical amplifiers and tunable UC lasers. (c) 2008 American Institute of Physics.

Judd-Ofelt analysis of spectra and experimental evaluation of laser performance of Tm3+ doped Lu2SiO5 crystal

This paper reports that the TM3+:Lu2SiO5 (Tm:LSO) crystal is grown by Czochralski technique. The room-temperature absorption spectra of Tm:LSO crystal are measured on a b-cut sample with 4 at.% thulium. According to the obtained Judd-Ofelt intensity parameters Omega(2)=9.3155 x 10(-20) cm(2), Omega(4)=8.4103 x 10(-20) cm(2), Omega(6)=1.5908 x 10(-20) cm(2), the fluorescence lifetime is calculated to be 2.03 ms for F-3(4) -> H-3(6) transition, and the integrated emission cross section is 5.81 x 10(-18) cm(2). Room-temperature laser action near 2 mu m under diode pumping is experimentally evaluated in Tm:LSO. An optical-optical conversion efficiency of 9.1% and a slope efficiency of 16.2% are obtained with continuous-wave maximum output power of 0.67 W. The emission wavelengths of Tm:LSO laser are centred around 2.06 mu m with spectral bandwidth of similar to 13.6 nm.