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arXiv · 0804.2548

Role of Frustration and Dimensionality in the Hubbard Model on the Stacked Square Lattice: Variational Cluster Approach

Toshihiko Yoshikawa·Masao Ogata
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Abstract

Using variational cluster approach, we study influence of frustration and dimensionality on magnetic properties in the ground state of Hubbard model on a stacked square lattice in the large $U$ region (U/t=10), by changing the next-nearest-neighbor hopping, $t^{\prime}$, and the interlayer hopping, $t_{\perp}$. For small $t_{\perp} t^{\prime}_{c_{2}}$. They are separated by a paramagnetic Mott insulating state which appears in the parameter region $t^{\prime}_{c_{1}} t^{\ast}_{\perp}$, the paramagnetic Mott insulating state disappears and a direct transition between antiferromagnetic state and collinear magnetic state occurs at $t^{\prime}=t^{\prime}_{c_{3}}$. We also find that the transition from the antiferromagnetic state to the paramagnetic Mott insulating state is of the second-order and that from the collinear magnetic state to the paramagnetic Mott insulating or the antiferromagnetic state is of the first-order.

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Toshihiko Yoshikawa, Masao Ogata. 2008-04-16. Role of Frustration and Dimensionality in the Hubbard Model on the Stacked Square Lattice: Variational Cluster Approach. https://doi.org/10.1103/physrevb.79.144429

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