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arXiv · 1408.4879

Magnetic phase diagram and Mott transition of the half-filled 1/5-depleted Hubbard model with frustration

Atsushi Yamada
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Abstract

The magnetic properties and Mott transition of the half-filled Hubbard model on the 1/5 depleted square lattice with frustration is studied at zero temperature by the variational cluster approximation. The $(\pi,\pi)$ N\'eel ordering (AF) is stable in a wide region of the phase diagram and almost completely veils the non-magnetic Mott transition for the unfrustrated case. However, AF is severely suppressed by the frustration and even with moderate frustrations the non-magnetic Mott transition takes place in the range where the intra-dimer hoppings are larger than the intra-plaquette hoppings.

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Atsushi Yamada. 2014-08-21. Magnetic phase diagram and Mott transition of the half-filled 1/5-depleted Hubbard model with frustration. https://doi.org/10.1103/physrevb.90.245139

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