• 文献标题:   Hexagonal Network of Photocurrent Enhancement in Few-Layer Graphene/InGaN Quantum Dot Junctions
  • 文献类型:   Article
  • 作  者:   CHENG GH, JIN ZJ, ZHAO CY, ZHOU CJ, LI BK, WANG JN
  • 作者关键词:   strain, graphene, ingan quantum dot, optoelectronic, flexoelectricity, electromechanical coupling
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:  
  • 被引频次:   1
  • DOI:   10.1021/acs.nanolett.2c01766 EA AUG 2022
  • 出版年:   2022

▎ 摘  要

Strain in two-dimensional (2D) materials has attracted particular attention because of the remarkable modification of electronic and optical properties. However, emergent electromechanical phenomena and hidden mechanisms, such as strain-superlattice-induced topological states or flexoelectricity under strain gradient, remain under debate. Here, using scanning photocurrent microscopy, we observe significant photo -current enhancement in hybrid vertical junction devices made of strained few-layer graphene and InGaN quantum dots. Optoelectronic response and photoluminescence measurements demonstrate a possible mechanism closely tied to the flexoelectric effect in few-layer graphene, where the strain can induce a lateral built-in electric field and assist the separation of electron-hole pairs. Photocurrent mapping reveals an unprecedentedly ordered hexagonal network, suggesting the potential to create a superlattice by strain engineering. Our work provides insights into optoelectronic phenomena in the presence of strain and paves the way for practical applications associated with strained 2D materials.