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摘要: 测量了在不同氧压下退火生长的YBa2Cu3O7-x(YBCO)薄膜中的激光感生热电电压(LITV)信号，发现随退火氧压的增大可使LITV信号的峰值有2—4倍的增强，并且变化趋势与薄膜热电势的各向异性随氧含量的变化规律相同.波长在473—808nm范围内的连续激光辐照，在5000Pa的氧压下退火生长的YBCO薄膜中探测到的LITV信号最大；而紫外脉冲激光辐照时，LITV信号的最大值出现在退火氧压为105Pa
Abstract: The laser-induced thermoelectric voltage (LITV) signals were measured in the YBa2Cu3O7-x (YBCO) films annealed under different oxygen pressure. It was found that the detected LITV signals were enhanced 2—4 times with the increasing of annealing oxygen pressure. The effect can be explained by the dependence of thermoelectric anisotropy on the oxygen content in YBCO. When the films were illuminated by continuous lasers in the wavelength range of 473—808nm， the measured signals in the films annealed under 5000Pa oxygen pressure were larger than those in other films. Meanwhile， pulse ultraviolet laser illumination produced the largest signal in the films annealed under oxygen pressure of 105Pa. The response time of LITV signals was observed to become shorter with the increasing of annealing oxygen pressure， which was shown to have resulted from the increasing of thermal conductivity theoretically. The films annealed under 5000Pa oxygen pressure had the fastest response to the pulsed ultraviolet laser. The response time was 70ns and the rise time of 29ns was comparable to the duration of the applied laser pulse (about 28ns).
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