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该文研究了在新型压电材料YCa4O(BO3)3(YCOB)上设计和制备高温声表面波(SAW)谐振器。研究了2种不同切型X-90°、Z-90°YCOB为基底的SAW谐振器的高温性能。研究表明,在600℃下器件的稳定性高,其谐振频率随着温度的升高呈线性降低。Z-90°YCOB器件的谐振频率和温度灵敏度分别为278.94 MHz和21.22kHz/℃;X-90°YCOB器件的谐振频率和温度灵敏度分别为230.53MHz和13.44kHz/℃。结果表明,Z-90°切型的YCOB的温度灵敏度较高。 相似文献
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YCOB晶体生长与激光倍频性能研究 总被引:2,自引:0,他引:2
坩埚下降法沿<010>和<001>方向生长了直径达到25mm的完整透明的Ca4YO(BO3)3 (YCOB)晶体.化学腐蚀结果表明,所生长晶体无孪晶或亚晶界等缺陷,晶体尾部的位错密度 不超过1800/cm2测量了YCOB的透射光谱,其截止波长为200nm进行了YCOB晶体对 Nd:YAG激光的二次倍频实验.通过与KDP晶体对比,计算出YCOB晶体的有效非线性系数 在Ⅰ型相位匹配方向(θ,φ)=(66.3°,143.5°)和(65.9°,36.5°)上分别为1.45pm/V和0.91pm/V; 大于KDP和 LBO晶体.在脉冲宽度10ns的 Nd:YAG激光单脉冲辐射下YCOB晶体出现体 损伤的激光损伤阈值不低于85GW/cm2. 相似文献
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Recently new borate crystals, CsLiB6O10 (CLBO), YCa4O(BO3)3 (YCOB) and Gd
x
Y1−x
Ca4O(BO3)3 (Gd
x
Y1−x
COB) have been developed by the present authors. Here, the growth and nonlinear optical properties of CLBO, YCOB and Gd
x
Y1−x
COB crystals are reviewed and their properties are discussed in relation to those of other nonlinear optical crystals, such
asβ-BaB2O4 (BBO), and LiB3O5 (LBO). 相似文献
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《中国稀土学报(英文版)》2019,37(9):924-930
FTIR absorption spectra indicate that H+ can easily enter the crystal structure and form OH-centers in Er:Yb:YCOB and O—H bonds prefer to lie in the a-c plane. Within our current studied concentration level,crystal samples with higher OH-abso rption coefficie nts demonstrate stro nger fluo rescence intensity and longer fluorescence lifetime at 1535 nm. As the stretching vibration energy of OH-group approximately corresponds to the energy gap between the ~4 I_(11/2) and ~4 I_(13/2) levels of Er~(3+), and thus, OH-ions can shorten the fluorescence lifetime of Er~(3+)-~4I_(11/2) level by the phonon-assisted cross-relaxation process between the Er~(3+) and OH-ions. Our curre nt results confirm that a certain conte nt of OH ions can enhance the ene rgy transfer process from Yb~(3+) to Er~(3+) and subsequently promote fluorescence output in 1.5-1.6 μm. 相似文献
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The high resolution spectral data on Nd3+ and Yb3+ in rare earth (RE) oxoborates RCa4O(BO3)3—with R3+ = Gd3+ and Y3+ are analyzed in terms of the disordered structure of these crystals proposed recently. A mixed occupancy of R3+ and Ca2+(1) sites creates the disorder that increases with decreasing the rare earth ionic radii. This mixed occupancy is valid for dopants too and creates “charge defects” in crystals. The disorder is spectrally manifested by minor sites and prevailing centers lineshapes and broadenings. Spectral characteristics of a minor site, observed in Nd3+ and Yb3+ spectra of both crystals, are qualitatively in accord with the proposed structure. The effects of mixed occupancy of the cationic sites in RCOB on rare earth dopants in R3+ sites is also analyzed. The possible activator centers probabilities, function on RCOB structure, that lead to lineshapes and widths are estimated. 相似文献
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基于YCOB晶体分析信号光脉冲时间特性对光参变啁啾脉冲放大光谱和转换效率的影响 总被引:1,自引:0,他引:1
基于YCOB晶体中三波耦合方程理论模型,在抽运光波形和能量、晶体长度相同的条件下,研究信号光的时间波形对光参变啁啾脉冲放大(OPCPA)光谱和转换效率的影响。计算过程中,抽运光和信号光能量分别为45J和500mJ,光斑直径分别为60mm和50mm。抽运光脉宽取3ns,信号光脉宽为1.2ns。数值结果显示,信号光放大后的光谱和转换效率与输入信号光的时间波形有关。1阶高斯型脉冲光谱的半峰全宽(FWHM)得以展宽,由原来的36nm展宽为放大后的61nm,2阶超高斯脉冲频谱展宽为47nm,高斯脉冲的阶数越高,谱宽展宽越小,5阶和5阶以上的高斯脉冲光谱不再展宽,几乎保持原来36nm不变;1阶高斯脉冲的转换效率最高,达到32%左右,2阶高斯脉冲只有25%,8阶以上转换效率基本变化不大,约为19%。信号光脉冲时间特性对OPCPA的光谱输出和转换效率产生很大的影响。 相似文献
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