Direct imaging and electronic structure modulation of moiré superlattices at the 2D/3D interface

Abstract

The atomic structure at the interface between two-dimensional (2D) and three-dimensional (3D) materials influences properties such as contact resistance, photo-response, and high-frequency electrical performance. Moiré engineering is yet to be utilized for tailoring this 2D/3D interface, despite its success in enabling correlated physics at 2D/2D interfaces. Using epitaxially aligned MoS2/Au{111} as a model system, we demonstrate the use of advanced scanning transmission electron microscopy (STEM) combined with a geometric convolution technique in imaging the crystallographic 32 Å moiré pattern at the 2D/3D interface. This moiré period is often hidden in conventional electron microscopy, where the Au structure is seen in projection. We show, via ab initio electronic structure calculations, that charge density is modulated according to the moiré period, illustrating the potential for (opto-)electronic moiré engineering at the 2D/3D interface. Our work presents a general pathway to directly image periodic modulation at interfaces using this combination of emerging microscopy techniques.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 26, 2021
Source ID
10.1038/s41467-021-21363-5

Entities

People

  • Abinash Kumar
  • Arthur M. Blackburn
  • Frances M. Ross
  • Georgios Varnavides
  • James M. LeBeau
  • Joachim Dahl Thomsen
  • Kate Reidy
  • Polina Anikeeva
  • Prineha Narang
  • Thang Q. Pham

Organizations

  • Gordon and Betty Moore Foundation
  • Independent Research Fund Denmark
  • National Science Foundation
  • Office of Naval Research

Tags

Fields of Study

  • Physics

Readers

  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene