Engineering Bandgaps of Monolayer MoS2 and WS2 on Fluoropolymer Substrates by Electrostatically Tuned Many-Body Effects

Bo Liu; Weijie Zhao; Zijing Ding; Ivan Verzhbitskiy; Linjun Li; Junpeng Lu; Jianyi Chen; Goki Eda; Kian Ping Loh

doi:10.1002/adma.201504876

Engineering Bandgaps of Monolayer MoS2 and WS2 on Fluoropolymer Substrates by Electrostatically Tuned Many-Body Effects

Adv Mater. 2016 Aug;28(30):6457-64. doi: 10.1002/adma.201504876. Epub 2016 May 17.

Authors

Bo Liu^{1

2}, Weijie Zhao^{2

3}, Zijing Ding^{1

4}, Ivan Verzhbitskiy³, Linjun Li^{1

2}, Junpeng Lu³, Jianyi Chen¹, Goki Eda^{1

2

3}, Kian Ping Loh^{1

2}

Affiliations

¹ Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore.
² Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, 6 Science Drive 2, 117546, Singapore.
³ Department of Physics, National University of Singapore, 2 Science Drive 3, 117542, Singapore.
⁴ SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, P. R. China.

PMID: 27184600
DOI: 10.1002/adma.201504876

Abstract

Intrinsic electrical and excitonic properties of monolayer transition-metal dichalcogenides can be revealed on CYTOP fluoropolymer substrates with greatly suppressed unintentional doping and dielectric screening. Ambipolar transport behavior is observed in monolayer WS2 by applying solid-state back gates. The excitonic properties of monolayer MoS2 and WS2 are determined by intricate interplays between the bandgap renormalization, Pauli blocking, and carrier screening against carrier doping.

Keywords: CYTOP substrate; bandgap renormalization; excitons; monolayer transition-metal dichalcogenides; phase-space filling effect.