常态下Y-Ba-Cu-O薄膜激光响应的热电效应模型研究

Study on Normal State Thermoelectric Model for Laser-induced Response of Y-Ba-Cu-O Films

对倾斜基片上生长的Ｙ－Ｂａ－Ｃｕ－Ｏ薄膜在常态下激光响应的热电效应模型进行了深入研究。根据Ｙ－Ｂａ－Ｃｕ－Ｏ薄膜对激光吸收的特点，估算了激光穿透深度δ，建立了符合实际物理过程的薄膜非均匀“温度梯度场”和热电势分布。并提出了处理Ｙ－Ｂａ－Ｃｕ－Ｏ薄膜激光响应与薄膜热电势关系的热电势并联模型，从而在理论上较好地解决了一般理论推导的矛盾。本模型提出的信号响应幅度与薄膜厚度关系、激光穿透深度及其相关处理方法均得到实验证实。

We studied the origin of laser-induced voltages in Y-Ba-Cu-O films based on thermoelectric effect. We pointed out that common explanation has a unsolved contradiction because of its even temperature-gradient presumption. We provided a physics model of parallel thermopower based on real physics process and absorption law of Y-Ba-Cu-O films for laser which shed light on the solution for this question of relation between magnitude of laser-response and thickness of the films. In addition, we obtained the Y-Ba-Cu-O absorption depth for laser through theoretical and experimental ways which were consistent with each other. Our results supported uneven temperature-gradient in the thermoelectric process of Y-Ba-Cu-O films.