Polaronic metal in lightly doped high-Tc cuprates

TL;DR

This paper combines ARPES experiments and quantum Monte Carlo simulations to identify a novel polaronic metallic state in underdoped cuprates, explaining key experimental puzzles related to electron-phonon interactions.

Contribution

It introduces an approximation scheme modeling underdoped cuprates as a single polaron with effective EPI, providing new insights into their electronic structure.

Findings

Explains momentum-dependent dichotomy in ARPES data.

Reproduces doping dependence of spectral features.

Proposes a polaronic metallic state as a new phase.

Abstract

We present a combined study of the angle-resolved-photoemission spectroscopy (ARPES) and quantum Monte Carlo simulations to propose a novel polaronic metallic state in underdoped cuprates. An approximation scheme is proposed to represent underdoped cuprates away from 1/2 filling, replacing the many-body Hamiltonian by that of a single polaron with effective electron-phonon interaction (EPI), that successfully explains many puzzles such as a large momentum-dependent dichotomy between nodal and anti-nodal directions, and an unconventional doping dependence of ARPES in the underdoped region.