Strain-enhanced trion emission in monolayer WS2 modulated by an ion-gel electrochemical gate

S Shou-Xin Zhao (School of Materials Science and Engineering, Harbin Institute of Technology 1 , Harbin 150001,) J Jia-Peng Wang (School of Materials Science and Engineering, Harbin Institute of Technology 1 , Harbin 150001,) Y Yue Liu L Liang Zhen (School of Materials Science and Engineering) Y Yang Li C Cheng-Yan Xu (Sauvage Laboratory for Smart Materials, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen) 2 , Shenzhen 518055,)

Abstract

The abundant light–matter interactions in monolayer WS2 make the manipulation of exciton states a fascinating endeavor. Utilizing photoluminescence spectroscopy, we investigated strain-induced red shifts and trion enhancement in a WS2 monolayer on a PET/PVA substrate with a Li+ ion-gel electrolyte gate. A notable red shift of the exciton emission peak was observed, increasing by ∼41 meV/%, up to a maximum strain of 2.5%. The combination of ion-gel and strain effectively modulated the radiative recombination, leading to a significant enhancement of the trion peak, with IXT/IX0 rising from 0.95 to 13.12 under 1.21% strain and 6.8 × 1012 cm−2 electron concentration. This enhancement is attributed to strain-induced changes in scattering channels between valleys and indirect bandgap excitation processes. Our study underscores the potential of coupling strain and ion-gate-induced doping for tuning excitonic behaviors in flexible quantum devices.

Article Details

Volume / Issue Vol. 126, Issue 22
Published June 02, 2025
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (6)

S

Shou-Xin Zhao

School of Materials Science and Engineering, Harbin Institute of Technology 1 , Harbin 150001,

J

Jia-Peng Wang

School of Materials Science and Engineering, Harbin Institute of Technology 1 , Harbin 150001,

Y

Yue Liu

L

Liang Zhen

School of Materials Science and Engineering

Y

Yang Li

C

Cheng-Yan Xu

Sauvage Laboratory for Smart Materials, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen) 2 , Shenzhen 518055,