Band Gap Engineering with Ultralarge Biaxial Strains in Suspended Monolayer MoS2

David Lloyd, Xinghui Liu, Jason W. Christopher, Lauren Cantley, Anubhav Wadehra, Brian L. Kim, Bennett B. Goldberg, Anna K. Swan, J. Scott Bunch*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

239 Scopus citations

Abstract

We demonstrate the continuous and reversible tuning of the optical band gap of suspended monolayer MoS2 membranes by as much as 500 meV by applying very large biaxial strains. By using chemical vapor deposition (CVD) to grow crystals that are highly impermeable to gas, we are able to apply a pressure difference across suspended membranes to induce biaxial strains. We observe the effect of strain on the energy and intensity of the peaks in the photoluminescence (PL) spectrum and find a linear tuning rate of the optical band gap of 99 meV/%. This method is then used to study the PL spectra of bilayer and trilayer devices under strain and to find the shift rates and Grüneisen parameters of two Raman modes in monolayer MoS2. Finally, we use this result to show that we can apply biaxial strains as large as 5.6% across micron-sized areas and report evidence for the strain tuning of higher level optical transitions.

Original languageEnglish (US)
Pages (from-to)5836-5841
Number of pages6
JournalNano letters
Volume16
Issue number9
DOIs
StatePublished - Sep 14 2016

Keywords

  • MoS
  • Raman spectroscopy
  • Strain engineering
  • bandgap
  • biaxial strain
  • photoluminescence

ASJC Scopus subject areas

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Fingerprint

Dive into the research topics of 'Band Gap Engineering with Ultralarge Biaxial Strains in Suspended Monolayer MoS<sub>2</sub>'. Together they form a unique fingerprint.

Cite this