Zhang Xuran, Dai Mingjin, Deng Wenjie, Zhang Yongzhe, Wang Qi Jie
School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Key Laboratory of Optoelectronics Technology, Ministry of Education, Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China.
Nanophotonics. 2023 Jan 11;12(3):607-618. doi: 10.1515/nanoph-2022-0660. eCollection 2023 Feb.
Self-powered photodetectors with broadband and polarization-sensitive photoresponse are desirable for many important applications such as wearable electronic devices and wireless communication systems. Recently, two-dimensional (2D) materials have been demonstrated as promising candidates for self-powered photodetectors owing to their advantages in light-matter interaction, transport, electronic properties, and so on. However, their performance in speed, broadband response, and multifunction is still limited. Here, we report a PdSe photodetector with asymmetric van der Waals (vdWs) contacts formed by using a homojunction configuration. This device achieves a high responsivity approaching 53 mA/W, a rise/decay time of about 0.72 ms/0.24 ms, and a detectivity of more than 5.17 × 10 Jones in the visible-near infrared regime (532-1470 nm). In addition, a linear polarization-sensitive response can be observed with an anisotropy ratio of 1.11 at 532 nm and 1.62 at 1064 nm. Furthermore, a strong anisotropic response endows this photodetector with outstanding polarization imaging capabilities, realizing a contrast-enhanced degree of linear polarization imaging. Our proposed device architecture demonstrated the great potential of PdSe-based asymmetric vdWs contacts for high-performance photodetectors operating without any external bias.
具有宽带和偏振敏感光响应的自供电光电探测器在许多重要应用中都很有需求，如可穿戴电子设备和无线通信系统。最近，二维（2D）材料因其在光与物质相互作用、传输、电子特性等方面的优势，已被证明是自供电光电探测器的有前途的候选材料。然而，它们在速度、宽带响应和多功能方面的性能仍然有限。在此，我们报告一种通过使用同质结配置形成不对称范德华（vdWs）接触的PdSe光电探测器。该器件在可见-近红外波段（532-1470nm）实现了接近53 mA/W的高响应度、约0.72 ms/0.24 ms的上升/下降时间以及超过5.17×10琼斯的探测率。此外，在532nm处各向异性比为1.11，在1064nm处为1.62时，可以观察到线性偏振敏感响应。此外，强烈的各向异性响应赋予该光电探测器出色的偏振成像能力，实现了对比度增强的线性偏振成像。我们提出的器件架构展示了基于PdSe的不对称vdWs接触对于无需任何外部偏置即可工作的高性能光电探测器的巨大潜力。
