Nano-optical Visualization of Interlayer Interactions in WSe2/WS2 Heterostructures

0558476 - ÚFCH JH 2023 RIV US eng J - Journal Article
Rodriguez, Álvaro - Krayev, A. V. - Velický, Matěj - Frank, Otakar - El-Khoury, Z.
Nano-optical Visualization of Interlayer Interactions in WSe2/WS2 Heterostructures.
Journal of Physical Chemistry Letters. Roč. 13, č. 25 (2022), s. 5854-5859. ISSN 1948-7185
R&D Projects: GA ČR(CZ) GA22-04408S; GA ČR(CZ) GX20-08633X
Institutional support: RVO:61388955
Keywords : Phonon * Raman scattering * Valley polarization
OECD category: Physical chemistry
Impact factor: 5.7, year: 2022
Method of publishing: Limited access

The interplay between excitons and phonons governs the optical and electronic properties of transition metal dichalcogenides (TMDs). Even though a number of linear and nonlinear optical-, electron-, and photoelectron-based approaches have been developed and/or adopted to characterize excitons and phonons in single/few-layer TMDs and their heterostructures, no existing method is capable of directly probing ultralow-frequency and interlayer phonons on the nanoscale. To this end, we developed ultralow-frequency tip-enhanced Raman spectroscopy, which allows spectrally and spatially resolved chemical and structural nanoimaging of WSe2/WS2 heterostructures. In this work, we apply this method to analyze phonons in nanobubbles that are sustained in these heterobilayers. Our method is capable of directly probing interlayer (de)coupling using our novel structurally sensitive nano-optical probe and the interplay between excitons and interlayer/intralayer phonons through correlation analysis of the recorded spectral images.
Permanent Link: http://hdl.handle.net/11104/0332122