Eur. Phys. J. B (2016) 89: 38
https://doi.org/10.1140/epjb/e2016-60785-3

Regular Article

Character of frustration on magnetic correlation in doped Hubbard model

¹ Department of Physics, Beijing Normal University, Beijing 100875, P.R. China
² Department of Physics, University of California, San Diego, California 92093, USA

^a e-mail: liang@bnu.edu.cn

Received: 5 October 2015
Received in final form: 22 December 2015
Published online: 10 February 2016

Abstract

The magnetic correlation in the Hubbard model on a two-dimensional anisotropic triangular lattice is studied by using the determinant quantum Monte Carlo method. Around half filling, it is found that the increasing frustration t^′/t could change the wave vector of maximum spin correlation along (π,π) → (π, 5π/6) → (5π/6, 5π/6) → (2π/3, 2π/3), indicating the frustration’s remarkable effect on the magnetism. In the studied filling region ⟨n⟩ = 1.0 − 1.3, the doping behaves like some kinds of frustration, which destroys the (π,π) AFM correlation quickly and push the magnetic order to a wide range of the (2π/3, 2π/3)120^° order when the t^′/t is large enough. Our non-perturbative calculations reveal a rich magnetic phase diagram over both the frustration and electron doping.