Exciton transport in strained monolayer WSe2

Abstract

We experimentally demonstrate the visualization of exciton energy transport in a non-uniformly strained WSe2 monolayer by monitoring the propagation of exciton densities via spectrally, temporally, and spatially resolved photoluminescence measurements at room temperature. Our measurements indicate that excitons in the WSe2 monolayer exhibit anomalous diffusion due to disorder in the system, which leads to a time-varying diffusion coefficient. In addition, we show that the sensitivity of monolayer WSe2's bandgap to strain gives rise to a built-in excitonic potential that results in the funneling of excitons towards high tensile strain points. The observed drift and diffusion agree reasonably with our proposed model that takes into account the strain field on the monolayer to describe the exciton dynamics.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 17, 2018
Source ID
10.1063/1.5063263

Entities

People

  • Che-Hsuan Cheng
  • Darwin F. Cordovilla Leon
  • Parag B. Deotare
  • Sung Woon Jang
  • Zidong Li

Organizations

  • Air Force Office of Scientific Research
  • National Science Foundation
  • University of Michigan

Tags

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene