arXiv:1804.08135 · Physical review. B./Physical review. B
Phase competition in a one-dimensional three-orbital Hubbard-Holstein model
Shaozhi Li, Yanfei Tang, Thomas Maier, Steven Johnston
Abstract
We study the interplay between the electron-phonon $(e$-ph) and on-site electron-electron (e-e) interactions in a three-orbital Hubbard-Holstein model on an extended one-dimensional lattice using determinant quantum Monte Carlo. For weak e-e and $e$-ph interactions, we observe a competition between an orbital-selective Mott phase (OSMP) and a (multicomponent) charge-density-wave (CDW) insulating phase, with an intermediate metallic phase located between them. For large e-e and $e$-ph couplings, the OSMP and CDW phases persist, while the metallic phase develops short-range orbital correlations and becomes insulating when both the e-e and $e$-ph interactions are large but comparable. Many of our conclusions are in line with those drawn from a prior dynamical mean-field theory study of the two-orbital Hubbard-Holstein model [Phys. Rev. B 95, 121112(R) (2017)] in infinite dimension, suggesting that the competition between the $e$-ph and e-e interactions in multiorbital Hubbard-Holstein models leads to rich physics, regardless of the dimension of the system.