Polarization‐Resolved Broadband MoS2/Black Phosphorus/MoS2 Optoelectronic Memory with Ultralong Retention Time and Ultrahigh Switching Ratio. (31st March 2021)

• Record Type: Journal Article
• Authors: Liu, Chang; Zou, Xuming; Wu, Min‐Ci; Wang, Yang; Lv, Yawei; Duan, Xinpei; Zhang, Sen; Liu, Xingqiang; Wu, Wen‐Wei; Hu, Weida; Fan, Zhiyong; Liao, Lei
• Is Part Of: Advanced functional materials. Volume 31:Number 23(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-03-31
• Subjects: black phosphorus -- broadband response -- MoS 2 -- multi‐bit memories -- polarization resolved; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202100781
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: The rapidly emerging requirement for device miniaturization and structural flexibility make 2D semiconductors and their van der Waals (vdWs) heterostructures extremely attractive for nonvolatile optoelectronic memory (NOM) applications. Although several concepts for 2D NOM have been demonstrated, multi‐heterojunction devices capable of further improving storage performance have received little attention. This work reports a concept for MoS2 /black phosphorus (BP)/MoS2 multi‐heterojunction NOM with artificial trap sites through the BP oxidation, in which the trapped holes at BP/PO x interface intrigue a persistent photoconductivity that hardly recovers within the experimental time scales (exceeding 10 4 s). As a result of the interfacial trap‐controlled charge injection, the device exhibits excellent photoresponsive memory characteristics, including a record high detectivity of ≈1.2 × 10 16 Jones, a large light‐to‐dark switching ratio of ≈1.5 × 10 7, an ultralow off‐state current of ≈1.2 pA, and an outstanding multi‐bit storage capacity (11 storage states, 546 nC state –1 ). In addition, the middle BP layer in the multi‐heterojunction enables broadband spectrum distinction (375–1064 nm), together with a high polarization ratio of 8.4. The obtained results represent the significant step toward the high‐density integration of optoelectronic memories with 2D vdWs heterostructures. Abstract : Here, the polarization‐resolved broadband MoS2 /black phosphorus/MoS2 optoelectronic memory is prepared by exploiting oxidation induced defects in black phosphorus layer. As a result of interfacial trap‐controlled charge injection, the device exhibits an ultrahigh responsivity of 1.3 × 10 7 A W −1, an ultralong retention time exceeding 6 × 10 4 s, together with an excellent multi‐bit storage capacity.