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arXiv · 0809.2383

Zero-temperature Phase Diagram of Two Dimensional Hubbard Model

K. Inaba·A. Koga·S. Suga·N. Kawakami
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Abstract

We investigate the two-dimensional Hubbard model on the triangular lattice with anisotropic hopping integrals at half filling. By means of a self-energy functional approach, we discuss how stable the non-magnetic state is against magnetically ordered states in the system. We present the zero-temperature phase diagram, where the normal metallic state competes with magnetically ordered states with $(π, π)$ and $(2π/3, 2π/3)$ structures. It is shown that a non-magnetic Mott insulating state is not realized as the ground state, in the present framework, but as a meta-stable state near the magnetically ordered phase with $(2π/3, 2π/3)$ structure.

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K. Inaba, A. Koga, S. Suga, N. Kawakami. 2008-09-14. Zero-temperature Phase Diagram of Two Dimensional Hubbard Model. https://doi.org/10.1088/1742-6596/150/4/042066

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