Electron-phonon coupling across the TMD/hBN van der Waals interface

G. Gatti; C. Berthod; J. Issing; M. Straub; S. Mandloi; Y. Alexanian; J. Avila; P. Dudin; T. K. Kim; M. D. Watson; C. Cacho; K. Watanabe; T. Taniguchi; W. Wang; N. Clark; R. Gorbachev; N. Ubrig; I. Gutierrez-Lezama; A. F. Morpurgo; A. Tamai; F. Baumberger

arXiv · 2604.24139

Electron-phonon coupling across the TMD/hBN van der Waals interface

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Abstract

Many-body interactions can couple electronic states in one layer with collective excitations in the adjacent layer, providing a route to tailor properties of heterostructures. However, detecting and quantifying interlayer many-body interactions proved a major challenge. Here, we demonstrate that quasiparticles in monolayer transition metal dichalcogenides (TMDs) are dressed by a remote cloud of phonons in the adjacent hexagonal boron nitride slab. Using angle resolved photoemission, we identify replica bands in the TMDs which are a clear fingerprint of long-range electron-phonon interaction. We develop a modified Fr\"ohlich model that shows semi-quantitative agreement with the experimental spectral functions. Our analysis shows that remote electron-phonon coupling is a generic property of interfaces with hBN. This has implications for electron mobilities in 2D materials, for superconductivity and possibly for moir\'e correlated phases.

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G. Gatti, C. Berthod, J. Issing, M. Straub, S. Mandloi, Y. Alexanian, J. Avila, P. Dudin, T. K. Kim, M. D. Watson, C. Cacho, K. Watanabe, T. Taniguchi, W. Wang, N. Clark, R. Gorbachev, N. Ubrig, I. Gutierrez-Lezama, A. F. Morpurgo, A. Tamai, F. Baumberger. 2026-04-27. Electron-phonon coupling across the TMD/hBN van der Waals interface. https://arxiv.org/abs/2604.24139

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