Interactions of electrons and Rydberg excitons in two-dimensional semiconductors

TL;DR

This paper introduces the concept of Rydberg attractive polarons in two-dimensional semiconductors, revealing how electron interactions hybridize excitons and provide insights into correlated electronic states.

Contribution

It presents a theoretical analysis showing electron-mediated hybridization of excitons, leading to the discovery of Rydberg attractive polarons in 2D materials.

Findings

Spectra explained by electron-mediated hybridization of excitons

Identification of Rydberg attractive polarons as a new many-body state

Enhanced understanding of electron-exciton interactions in 2D semiconductors

Abstract

Rydberg excitons in two-dimensional semiconductors provide sensitive and non-destructive probes of physics in proximal sample layers that host correlated electronic states. In particular, electron or hole doping of the sample layer is heralded by a strong frequency shift and loss of transition strength of 2s excitons in the sensor layer; these features have been attributed to the formation of a bound state of a 2s exciton and a remote electron. Through a theoretical analysis of exciton-electron scattering, we show that the experimental spectra can only be explained by electron-mediated hybridization of 2s, 2p and interlayer excitons, leading to a new type of many-body state which we term Rydberg attractive polaron. We anticipate that this new understanding will ensure a more accurate assessment of the signatures of correlated electrons in two dimensional materials.