Highly Polarization-Sensitive, Broadband, Self-Powered Photodetector Based on Graphene/PdSe2/Germanium Heterojunction

Di Wu, Jiawen Guo, Juan Du, Congxin Xia, Longhui Zeng, Yongzhi Tian, Zhifeng Shi, Yongtao Tian, Xin Jian Li, Yuen Hong Tsang, Jiansheng Jie

Research output: Journal article publicationJournal articleAcademic researchpeer-review

85 Citations (Scopus)

Abstract

Polarization-sensitive photodetection in a broad spectrum range is highly desired due to the great significance in military and civilian applications. Palladium diselenide (PdSe2), a newly explored air-stable, group 10 two-dimensional (2D) noble metal dichalcogenide with a puckered pentagonal structure, holds promise for polarization-sensitive photodetection. Herein, we report a highly polarization-sensitive, broadband, self-powered photodetector based on graphene/PdSe2/germanium heterojunction. Owing to the enhanced light absorption of the mixed-dimensional van der Waals heterojunction and the effective carrier collection with graphene transparent electrode, the photodetector exhibits superior device performance in terms of a large photoresponsivity, a high specific detectivity, a fast response speed to follow nanosecond pulsed light signal, and a broadband photosensitivity ranging from deep ultraviolet (DUV) to mid-infrared (MIR). Significantly, highly polarization-sensitive broadband photodetection with an ultrahigh polarization sensitivity of 112.2 is achieved, which represents the best result for 2D layered material-based photodetectors. Further, we demonstrated the high-resolution polarization imaging based on the heterojunction device. This work reveals the great potential of 2D PdSe2 for high-performance, air-stable, and polarization-sensitive broadband photodetectors.

Original languageEnglish
Pages (from-to)9907-9917
Number of pages11
JournalACS Nano
Volume13
Issue number9
DOIs
Publication statusPublished - 1 Jan 2019

Keywords

  • broadband photodetection
  • heterojunction
  • PdSe
  • polarization-sensitive photodetector
  • two-dimensional materials

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

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