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Yb:GdVO4晶体是一种很好的激光材料,但缺陷会对晶体的激光性能产生严重影响,开展对该晶体的缺陷研究有助于提高晶体质量。采用提拉法生长了面25mm×20mm,掺杂浓度为2%的Yb:GdVO4晶体;分析了晶体的结构及其对晶体解理性的影响;采用化学腐蚀法,以盐酸、氢氟酸为腐蚀剂,对晶体的主要晶面进行了化学腐蚀实验,通过其腐蚀坑形貌对晶体中的位错和晶界进行了研究;对晶体进行了高分辨X衍射实验,结果表明晶体中存在镶嵌块结构;开裂及散射颗粒也为晶体中较常见缺陷。分析了缺陷的成因并提出了预防措施。 相似文献
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采用提拉法沿a轴和c轴生长出无色透明的GdVO4单晶,质量均超过50g.用X射线荧光分析法测得两个主要元素Gd和V的分凝系数都接近1.室温下测量了GdVO4晶体的X射线粉末衍射图,确定所获GdVO4晶体属于四方晶系,D194h-I41/amd空间群.通过晶体的锥光干涉图确定GdVO4晶体为单轴晶,光轴方向平行于c轴且光学均匀性比较好.利用高分辨X射线衍射仪测量GdVO4晶体的摇摆曲线,结果表明生长的GdVO4晶体的晶格完整性较好.通过浮力法测得其室温下密度为5.478g/cm3.透过波谱表明透过波长大于340nm. 相似文献
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用提拉法沿a轴和c轴成功生长出质量优良的Nd:YbVO4新型单晶.采用HRXRD-D5005型高分辨X射线衍射仪测得晶体的摇摆曲线,可以测得(400)面的半峰宽为70.92″,(004)面的半峰宽为19.80″.测得掺杂浓度为1;原子分数Nd:YbVO4晶体中Nd离子的有效分凝系数Keff为0.54.在298.15~573.15K温度范围内测量了晶体的热膨胀系数,αa=2.6×10-6/K,αb=2.5×10-6/K,αc=8.7×10-6/K;测得比热值为0.45~0.65J/g·K.测量了晶体的热扩散系数a,从而得到了其热导率λ. 相似文献
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Potassium tantalate niobate (KTa1-xNbxO3, KTN) crystals with different dimensions and quality situations were grown by Czochralski method. Crystal growth process and morphology properties of KTN are presented in this paper. It was found that some defects, such as bubble, inclusion, crack, dislocation etc., can all appear if the crystal is grown in an improper condition. The character and formation mechanism of such defects in macro growth are discussed. We consider that the CO2, which was not released absolutely during the sintering process and dissolved in the melt, led to bubbles. The composition of the inclusion caused by high pulling and rotation rates is KTN polycrystalline. The crack and dislocation in KTN crystal mainly come from improper temperature field. Etching and high-resolution X-ray diffraction (HRXRD) experiment results indicate that the central area is the defects concentrated. 相似文献
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Dysprosium-doped orthorhombic yttrium aluminate(Dy:YAlO3or Dy:YAP) single crystals were grown by the Czochralski method with a size of Φ43 mm × 150 mm. Based on the measurements of spectra and theoretical analysis, the white-light emission was investigated with different doping concentrations. The optimal white emission was achieved at Dy3+ doping concentration of 1.0% under 450 nm excitation. Combining with residual pumping light, the white-light output was successfully obtained with... 相似文献
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