Results in Physics

Ground-state instabilities in a Hubbard-type chain with particular correlated hopping at non-half-filling

Weiting Chen, Jun Zhang, Hanqin Ding

Published Apr 24, 2023• 5 citations

Abstract

At non-half-filling, a one-dimensional interacting electronic model (t–U–R) is studied analytically. The particular correlated hopping keeps particle–hole symmetry of the Hubbard model. Physically, the model involved is equivalent to an extended Hubbard chain incorporating a two-body (X) and a three-body (X˜) site-bond interactions with X˜=2X. The analysis of weak-coupling theory leads to the ground-state phase diagram, which consists of three types of metallic phases, characterized by the charge- (CDW) and spin-density-wave (SDW) and singlet-superconductivity (SS) instabilities.

DOI: 10.1016/j.rinp.2023.106472

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