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YAP晶体变色现象的研究 总被引:2,自引:0,他引:2
YAlO3(YAP)晶体具有优良的物理和化学性能,在许多方面都有广泛的应用前景.我们在对闪烁晶体Ce∶YAP的研究过程中,发现了YAP晶体的变色现象.本文利用晶体透过谱对其颜色的变化进行了研究.不同的退火气氛及不同的掺杂成份对晶体颜色有较大影响,H2气氛退火或掺杂Ce元素使晶体颜色变浅,而在空气中退火或掺杂Yb元素则使晶体颜色加深.针对这一变色现象,我们认为是在晶体生长过程由于电荷补偿的需要而产生的O-心的吸收作用导致的.不同的O-心浓度其吸收作用不同,从而使晶体在400nm附近的透过率发生变化.采用这一模型可以对晶体颜色的变化及不同退火条件和掺杂元素的影响作出合理的解释. 相似文献
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The Yb:YAG and Yb:YAP crystals have been grown by Czochralski method. The absorption spectra and the fluorescence spectra of Yb:YAG and Yb:YAP crystals have been investigated. It is shown that the Yb:YAG crystal has better laser properties and smaller threshold power than Yb:YAP crystal. In addition, the absorption cross-section of the Yb:YAP crystal is 2.16 times of that of the Yb:YAG crystal, so laser diode pumped Yb:YAG lasing can be easily realized. Because YAP single crystal is anisotropic, it is provided with polarization characteristics. 相似文献
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研究了两种磁悬浮系统组态中圆台形辅助永磁体厚度对高温超导体捕获磁场和超导磁悬浮力的影响。结果表明,圆台形辅助永磁体的下表面和GdBCO超导体上表面同处在一个水平面上,磁化用圆台形辅助永磁体的厚度H从5 mm增加到45 mm时,超导体捕获磁场和磁悬浮力与圆台形辅助永磁体的厚度直接相关。(1)当圆台形辅助永磁体的北极垂直向上且用液氮冷却后移除辅助永磁体时,最大磁悬浮力从21.8 N增大到26.5 N,再减小到22.9 N;(2)当圆台形辅助永磁体的北极垂直向下且用液氮冷却后移除辅助永磁体时,最大磁悬浮力从20.5 N减小到11.9 N ,再增加到20.4 N;(3)两种磁悬浮系统组态中最大磁悬浮力不一致,与零场冷情况下的最大磁悬浮力14.6 N也不同。在超导磁悬浮应用系统设计中,只有科学选择辅助永磁体形状和尺寸,合理设计组合方式,才能获得较强的磁场强度,提高超导磁悬浮力特性,该结果对促进高温超导体的实际应用具有重要的指导作用。 相似文献
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LiLuF4 single crystals co-doped with thulium (5%) and holmium (0.5%), having large size, intact shape, and high optical quality, are successfully grown by the Czochralski technique. Absorption and fluorescence spectra of the crystal are measured. The absorption spectrum shows that the main absorption band locates at near 686 and 792 nm and the fluorescence spectrum peaks at 2.05 um. At room temperature, the as-grown Tin, Ho: LiLuF4 single crystals are end-pumped by a fiber-coupled laser diode system with pumping wavelength of 795 nm under CW operations. A power of 50 mw contin- uous laser outout at 2.05-um wavelength is achieved. Meanwhile an obvious green light is detected. 相似文献
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