The transverse thermoelectric (TTE) effect of inclined thin films, originating from the anisotropy of the Seebeck coefficient of the films, has received extensive attention owing to its great application potential in self-powered photodetectors and heat flux sensors. In this paper, a novel TTE ultraviolet pulsed photodetector was constructed by using a high-quality c-axis inclined PbBi₂Te₄ thin film prepared on an SrTiO₃ substrate via a pulsed laser deposition technique. The device exhibited very high voltage sensitivity R_s as well as ultrafast response time, with an R_s of about 25.75 V/mJ and rise time of about 18 ns. In addition, the device showed long-term working stability in air after coating a thin layer of Al₂O₃ and perfect linearity with an R-squared coefficient close to 1. The results demonstrate that PbBi₂Te₄, a compound with large anisotropy of the Seebeck coefficient, is a new promising material for fabricating high-performance TTE-based ultraviolet pulsed photodetectors.

中文翻译：

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基于倾斜 PbBi2Te4 薄膜横向热电效应的超高灵敏度、高速紫外脉冲光电探测器


倾斜薄膜的横向热电 （TTE） 效应源于薄膜塞贝克系数的各向异性，由于其在自供电光电探测器和热通量传感器中的巨大应用潜力而受到广泛关注。本文利用脉冲激光沉积技术在 SrTiO₃ 衬底上制备的高质量 c 轴倾斜 PbBi₂Te₄ 薄膜，构建了一种新型 TTE 紫外脉冲光电探测器。该器件表现出非常高的电压灵敏度 R_s 和超快的响应时间，R_s 约为 25.75 V/mJ，上升时间约为 18 ns。此外，该装置在涂覆一层薄薄的 Al₂O₃ 后，在空气中表现出长期工作稳定性，并且 R 平方系数接近 1，线性度完美。结果表明，PbBi₂Te₄ 是一种塞贝克系数各向异性较大的化合物，是制造高性能基于 TTE 的紫外脉冲光电探测器的新型有前途的材料。