Neutral and charged excitons interplay in non-uniformly strain-engineered WS${}_2$

Abstract

We investigate the response of excitons in two-dimensional semiconductors subjected to controlled non-uniform strain fields. In our approach to non-uniform strain-engineering, a WS${}_2$ monolayer is suspended over a triangular hole. Large ($>2\%$), strongly non-uniform ($>0.28\%/\mu m$), and in-situ tunable strain is induced in the monolayer by pressurizing it with inert gas. We observe peak shifts and spectral shape changes in the photoluminescence spectra of strained WS${}_2$. We interpret these changes as a signature of increased free electron density and resulting conversion of neutral excitons to trions in the region of high strain. Our result establishes non-uniform strain engineering as a novel and useful experimental `knob' for tuning optoelectronic properties of 2D semiconductors.

arXiv comment12 pages, 5 figures

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Cited by in corpus (5)

• Strain control of hybridization between dark and localized excitons in a 2D semiconductor
• Spatiotemporally Controlled Room Temperature Exciton Transport under Dynamic Pressure
• Mechanically-tunable bandgap closing in 2D graphene phononic crystals
• Limits of funneling efficiency in non-uniformly strained 2D semiconductors
• Angular Emission Properties of Strained Transition-Metal Dichalcogenides