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.
@article{arxiv.1109.4502,
title = {Polaronic metal in lightly doped high-Tc cuprates},
author = {A. S. Mishchenko and N. Nagaosa and K. M. Shen and Z. -X. Shen and X. J. Zhou and T. P. Devereaux},
journal= {arXiv preprint arXiv:1109.4502},
year = {2011}
}