Polarization-resolved black phosphorus/molybdenum disulfide mid-wave infrared photodiodes with high detectivity at room temperature

• Published in: Nature photonics Vol. 12; no. 10; pp. 601 - 607
• Main Authors: Bullock, James, Amani, Matin, Cho, Joy, Chen, Yu-Ze, Ahn, Geun Ho, Adinolfi, Valerio, Shrestha, Vivek Raj, Gao, Yang, Crozier, Kenneth B., Chueh, Yu-Lun, Javey, Ali
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.10.2018; Nature Publishing Group
• Subjects: 639/301/1005/1009; 639/624/1075/1082; 639/624/1075/401; Applied and Technical Physics; ENGINEERING; Heterojunctions; Infrared detectors; Molybdenum; Molybdenum disulfide; Optical properties; Optics; OTHER INSTRUMENTATION; Performance enhancement; Phosphorus; Photodiodes; Photometers; Physics; Physics and Astronomy; Polarization; Quantum Physics; Room temperature; Sensors
• ISSN: 1749-4885; 1749-4893
• DOI: 10.1038/s41566-018-0239-8

Infrared photodetectors are currently subject to a rapidly expanding application space, with an increasing demand for compact, sensitive and inexpensive detectors. Despite continued advancement, technological factors limit the widespread usage of such detectors, specifically, the need for cooling and the high costs associated with processing of iii – v / ii – vi semiconductors. Here, black phosphorous (bP)/MoS 2 heterojunction photodiodes are explored as mid-wave infrared (MWIR) detectors. Although previous studies have demonstrated photodiodes using bP, here we significantly improve the performance, showing that such devices can be competitive with conventional MWIR photodetectors. By optimizing the device structure and light management, we demonstrate a two-terminal device that achieves room-temperature external quantum efficiencies ( η e ) of 35% and specific detectivities ( D *) as high as 1.1 × 10 10  cm Hz 1/2  W −1 in the MWIR region. Furthermore, by leveraging the anisotropic optical properties of bP we demonstrate the first bias-selectable polarization-resolved photodetector that operates without the need for external optics. Black phosphorus/molybdenum disulfide mid-wave infrared photodiodes with external quantum efficiencies of 35% across 2.5–3.5 μm at room temperature and a peak detectivity of 1.1 × 10 10  cm Hz 1/2  W –1 at 3.8 μm are demonstrated.