PbSe is one of the most representative materials in lead chalcogenide semiconductors, possessing a narrow bandgap and demonstrating excellent absorption and photoresponse. However, undoped PbSe typically exhibits low carrier concentrations, along with large dielectric constants and thermal expansion coefficients, imposing limitations on its application in a high-performance photodetector. Doping is an effective strategy to overcome the inherent defects and enhance the optical and electrical properties. In this study, different compositions of Pb_1−xLa_xSe samples were obtained through solid-phase method doping with the rare earth element La. The doped Pb_0.7La_0.3Se showed superior optical and electrical properties and photoresponse. Additionally, based on the approach of constructing heterojunctions with thin films and two-dimensional (2D) materials, a self-powered p−n heterojunction photodetector, Pb_0.7La_0.3Se/WSe₂, has been successfully fabricated. The device exhibited a continuous and stable light response from 405 to 1550 nm. Moreover, under 0 V bias and 650 nm laser irradiation, the device achieved the responsivity and specific detectivity of 22.85 A/W and 1.81 × 10¹² Jones, along with a rapid response/recovery time (162/135 μs), demonstrating excellent photovoltaic effects and outstanding photodetection performance. The construction of heterojunctions with film and 2D materials provides a novel approach to achieving high-performance photodetectors. Simultaneously, the Pb_0.7La_0.3Se/WSe₂ detector shows enormous potential in the field of superior photodetectors with a high on/off ratio, low noise, broadband, rapid response, and miniaturization.

中文翻译：

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基于La掺杂PbSe薄膜异质结的高响应度、快速响应的自供电宽带光电探测器


PbSe是铅硫族半导体中最具代表性的材料之一，具有窄带隙并表现出优异的吸收和光响应。然而，未掺杂的 PbSe 通常表现出低载流子浓度，以及大的介电常数和热膨胀系数，这限制了其在高性能光电探测器中的应用。掺杂是克服固有缺陷并增强光电性能的有效策略。本研究通过固相法掺杂稀土元素La，得到了不同成分的Pb _1−x La _x Se样品。掺杂的Pb _0.7 La _0.3 Se表现出优异的光电性能和光响应性。此外，基于薄膜和二维（2D）材料构建异质结的方法，一种自供电p−n异质结光电探测器，Pb _0.7 La _0.3 Se/WSe ₂ ，已成功制作。该器件在 405 至 1550 nm 范围内表现出连续稳定的光响应。此外，在0 V偏压和650 nm激光照射下，该器件实现了22.85 A/W和1.81 × 10 ¹² Jones的响应度和比探测率，以及快速的响应/恢复时间（162/135 μs），表现出优异的光伏效应和出色的光电探测性能。用薄膜和二维材料构建异质结提供了一种实现高性能光电探测器的新方法。同时，Pb _0.7 La _0.3 Se/WSe ₂ 探测器在具有高开/关比、低噪声、宽带化、快速响应、小型化。