Excitonic Effects in Tungsten Disulfide Monolayers on Two-Layer Graphene

Cristina E. Giusca, Ivan Rungger, Vishal Panchal, Christos Melios, Zhong Lin, Yu Chuan Lin, Ethan Kahn, Ana Laura Elías, Joshua A. Robinson, Mauricio Terrones, Olga Kazakova

Research output: Contribution to journalArticlepeer-review

31 Scopus citations

Abstract

Light emission in atomically thin heterostructures is known to depend on the type of materials and the number and stacking sequence of the constituent layers. Here we show that the thickness of a two-dimensional substrate can be crucial in modulating the light emission. We study the layer-dependent charge transfer in vertical heterostructures built from monolayer tungsten disulfide (WS2) on one- and two-layer epitaxial graphene, unravelling the effect that the interlayer electronic coupling has on the excitonic properties of such heterostructures. We bring evidence that the excitonic properties of WS2 can be effectively tuned by the number of supporting graphene layers. Integrating WS2 monolayers with two-layer graphene leads to a significant enhancement of the photoluminescence response, up to 1 order of magnitude higher compared to WS2 supported on one-layer graphene. Our findings highlight the importance of substrate engineering when constructing atomically thin-layered heterostructures.

Original languageEnglish (US)
Pages (from-to)7840-7846
Number of pages7
JournalACS nano
Volume10
Issue number8
DOIs
StatePublished - Aug 23 2016

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'Excitonic Effects in Tungsten Disulfide Monolayers on Two-Layer Graphene'. Together they form a unique fingerprint.

Cite this