Proximity control of interlayer exciton-phonon hybridization in van der Waals heterostructures
Journal article, 2021

Van der Waals stacking has provided unprecedented flexibility in shaping many-body interactions by controlling electronic quantum confinement and orbital overlap. Theory has predicted that also electron-phonon coupling critically influences the quantum ground state of low-dimensional systems. Here we introduce proximity-controlled strong-coupling between Coulomb correlations and lattice dynamics in neighbouring van der Waals materials, creating new electrically neutral hybrid eigenmodes. Specifically, we explore how the internal orbital 1s-2p transition of Coulomb-bound electron-hole pairs in monolayer tungsten diselenide resonantly hybridizes with lattice vibrations of a polar capping layer of gypsum, giving rise to exciton-phonon mixed eigenmodes, called excitonic Lyman polarons. Tuning orbital exciton resonances across the vibrational resonances, we observe distinct anticrossing and polarons with adjustable exciton and phonon compositions. Such proximity-induced hybridization can be further controlled by quantum designing the spatial wavefunction overlap of excitons and phonons, providing a promising new strategy to engineer novel ground states of two-dimensional systems. Here, the authors demonstrate proximity-controlled strong-coupling between Coulomb correlations and lattice dynamics in neighbouring van der Waals materials (WSe2 and a gypsum layer), creating electrically neutral hybrid exciton-phonon eigenmodes called excitonic Lyman polarons.

Author

Philipp Merkl

University of Regensburg

Chaw-Keong Yong

University of Regensburg

Marlene Liebich

University of Regensburg

Isabella Hofmeister

University of Regensburg

Gunnar Berghäuser

Philipps University Marburg

Chalmers, Physics, Condensed Matter Theory

Ermin Malic

Philipps University Marburg

Chalmers, Physics, Condensed Matter and Materials Theory

Rupert Huber

University of Regensburg

Nature Communications

2041-1723 (ISSN)

Vol. 12 1 1719

Graphene Core Project 3 (Graphene Flagship)

European Commission (EC), 2020-04-01 -- 2023-03-31.

Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Condensed Matter Physics

DOI

10.1038/s41467-021-21780-6

PubMed

33741906

More information

Latest update

4/9/2021 1