Research on Intracavity Laser Cooling of Solid

A theoretical study of intra-cavity laser cooling by anti-Stokes luminescence in a rare-earth doped glass is performed. Compared with cooling in an external cavity by multipassing the radiation, intra-cavity cooling has the advantage of high pumping power and high-absorbed power. However, one must ensure that the cavity can still form a laser by locating the material in the cavity. A model is developed to evaluate the enhancement factor and the absorbed power. The results show that for a low optical density, especially when the sample length is less than 2ram, the intracavity configuration is a very efficient method for laser cooling. The diode laser, which may become the best candidate for our model, is briefly discussed.     

Luminescence Spectra of YGG：RE^3＋, Bi^3＋ （RE = Eu and Tb） and Energy Transfer from Bi^3＋ to RE^3＋

We investigate the luminescence properties of Bi^3＋ and RE^3＋ （RE = Tb or Eu） in a Y3Ga5O12 （YGG） host system. The additional doping of Bi^3＋ can enhance the luminescence of Th^3＋ or Eu^3＋ in this host. Energy transfer from Bi^3＋ to Tb^3＋ and Eu^3＋ is observed and the mechanism of energy transfer is investigated. Mechanism of energy transfer can be explained as electric multipole interaction since the Bi^3＋ emission band and Tb^3＋ or Eu^3＋ excitation band overlaps and the Bi^3＋ emission intensity decreases while the intensity of Tb^3＋ or Eu^3＋ increases with the increase of Tb^3＋ or Eu^3＋ concentration. Therefore, Bi^3＋ ion is a kind of efficient sensitizer to the Tb^3＋ and Eu^3＋ activators in the Y3Ga5O12 host.     

稀土元素原子发射光谱及其谱线干扰的高分辨率ICP-AES研究——Ⅲ镝基体对其他稀土元素的光谱干扰

本工作利用光栅刻线数为３６００条／ｍｍ的高分辨率ＩＣＰ－ＡＥＳ光谱仪，详细研究了镝（Ｄｙ）基体对其他１４个稀土元素共６６条“首选分析线”的光谱干扰情况     

XRF聚酯薄膜—薄纸片法测定微量稀土元素

本方法是用贴在聚酯薄膜上的薄纸片来控制样品面积和富集被测元素,可用于绝对量的X射线荧光光谱分析,可测定比普通滤纸片法要求溶液浓度低50—100倍的样品溶液。该方法使用计算机进行谱线干扰校正、背景扣除,并使用最小二乘法进行线性回归。此方法具有快速、简便、灵敏、准确的特点。     

Pb1—xEuxSeyTe1—y双异质结的分子束外延生长

用分子束外延技术在P型PbTe[100]衬底上成功地生长出Pb_(0.970)Eu_(0.030)Se_(0.016)Te_(0.984)/Pb_(0.970)Eu_(0.030)Se_(0.016)Te_(0.984)双异质结。为得到发射波长在2～4μm波段的半导体激光器,通过控制有源区Eu的组份(x值)来调节有源区的禁带宽度。经扫描电子显微镜分析及电学特性的测量,证明Pb_(1-x)Eu_xSe_yTe_(1-y)双异质结结构均匀完整,结特性明显。     

稀土元素对铝锌镁合金超塑性的影响

本文研究了RE对Al-Zn-Mg合金超塑变形机制的影响。晶粒取向因素也是增强超塑性效应的重要条件。通过对各种状态(铸态、再结晶态和超塑拉伸态等)的试样进行光学金相、定量金相、电子探针和X射线衍射等研究表明,RE存在于Al-Zn-Mg合金的晶界处,改善了合金的晶粒尺寸因素和晶粒取向因素,从而增强了合金的超塑性效应。