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arXiv · 1601.07504

Character of frustration on magnetic correlation in doped Hubbard model

Peng Wang·Xinran Ma·Jingyao Wang·Yamei Zeng·Ying Liang·Tianxing Ma
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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 ($\pi,\pi$)$\rightarrow$($\pi,\frac{5\pi}{6}$)$\rightarrow$($\frac{5\pi}{6},\frac{5\pi}{6}$)$\rightarrow$ ($\frac{2\pi}{3},\frac{2\pi}{3}$), indicating the frustration's remarkable effect on the magnetism. In the studied filling region =1.0-1.3, the doping behaves like some kinds of {\it{frustration}}, which destroys the $(\pi,\pi)$ AFM correlation quickly and push the magnetic order to a wide range of the $(\frac{2\pi}{3},\frac{2\pi}{3})$ $120^{\circ}$ 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.

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Peng Wang, Xinran Ma, Jingyao Wang, Yamei Zeng, Ying Liang, Tianxing Ma. 2016-01-27. Character of frustration on magnetic correlation in doped Hubbard model. https://doi.org/10.1140/epjb%2Fe2016-60785-3

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