Optical study of local strain related disordering in CVD-grown MoSe2 monolayers

Abstract

We present temperature dependent micro-photoluminescence and room temperature photoreflectance spectroscopy studies on aged MoSe2 monolayers with high surface roughness. A0 and B0 exciton bands were detected at 1.512 eV and 1.72 eV, respectively, which are 50–70 meV lower than those commonly reported for high-quality samples. It is shown that the difference can be accounted for using a model of localized excitons for disordered MoSe2 monolayers where the optical band gap energy fluctuations could be caused by random distribution of local tensile strain due to surface roughness. The density of localized exciton states is found to follow the Lorentzian shape, where the peak of this distribution is about 70 meV from the energy of delocalized states.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 19, 2016
Source ID
10.1063/1.4972782

Entities

People

  • B. Li
  • H.-p. Komsa
  • I. Sildos
  • J. Krustok
  • M. Marandi
  • Pulickel Ajayan
  • R. Jaaniso
  • T. Raadik
  • Valter Kiisk
  • Xiaoxuan Zhang
  • Yan Gong

Organizations

  • Aalto University
  • Estonian Research Competency Council
  • European Commission
  • Research Council of Finland
  • Rice University
  • Tallinn University of Technology
  • United States Army Armament Research, Development and Engineering Center
  • University of Tartu
  • Villanova University

Tags

Fields of Study

  • Physics

Readers

  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.
  • Semiconductor Device Technology

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene