Twist-angle dependence of moiré excitons in WS2/MoSe2 heterobilayers

Abstract

Moiré lattices formed in twisted van der Waals bilayers provide a unique, tunable platform to realize coupled electron or exciton lattices unavailable before. While twist angle between the bilayer has been shown to be a critical parameter in engineering the moiré potential and enabling novel phenomena in electronic moiré systems, a systematic experimental study as a function of twist angle is still missing. Here we show that not only are moiré excitons robust in bilayers of even large twist angles, but also properties of the moiré excitons are dependant on, and controllable by, the moiré reciprocal lattice period via twist-angle tuning. From the twist-angle dependence, we furthermore obtain the effective mass of the interlayer excitons and the electron inter-layer tunneling strength, which are difficult to measure experimentally otherwise. These findings pave the way for understanding and engineering rich moiré-lattice induced phenomena in angle-twisted semiconductor van der Waals heterostructures.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 18, 2020
Source ID
10.1038/s41467-020-19466-6

Entities

People

  • Danqing Wang
  • Fengcheng Wu
  • Hui Deng
  • Kenji Watanabe
  • Krishnamurthy Kulkarni
  • Long Zhang
  • Rahul Gogna
  • Shaocong Hou
  • Stephen R. Forrest
  • Takashi Taniguchi
  • Thomas Kuo
  • Zhe Zhang

Organizations

  • Army Research Office
  • Core Research for Evolutional Science and Technology
  • National Science Foundation

Tags

Fields of Study

  • Physics

Readers

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

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene