# Long living carriers in a strong electron-phonon interacting two-dimensional doped semiconductor

## TL;DR

This paper investigates the complex electron-phonon interactions in doped 2D semiconductors, revealing long-lived carriers despite strong interactions, through combined first-principles and analytic methods, with implications for transport properties.

## Contribution

It introduces a detailed analysis of many-body electron spectra in doped 2D materials, uncovering the physical origin of multiple quasi-particle states and their lifetimes.

## Key findings

- Identification of three quasi-particle states in doped MoS2
- Discovery of a long-lived state despite strong electron-phonon coupling
- Explanation of the physical origin of observed spectral gaps

## Abstract

Carrier doping by the electric field effect has emerged recently as an ideal route for monitoring many-body physics in two-dimensional (2D) materials where the Fermi level is tuned in a way that -- indirectly -- the strength of the interactions can also be scanned. The possibility of systematic doping in combination with high resolution photoemission has allowed to uncover a genuinely many-body electron spectrum in single-layer MoS2 transition metal dichalcogenide, resolving three clear quasi-particle states, where only one state should be expected if the electron-phonon interaction vanished. Our analysis combines first-principles and consistent complex plane analytic approaches and brings into light the presence and the physical origin of two gaps and the three quasi-particle bands which are unambiguously present in the photoemission spectrum. One of these states, though being strongly interacting with the accompanying virtual phonon cloud, presents a notably long lifetime which is an appealing property when trying to understand and take advantage of many-body interactions to modulate the transport properties.