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arXiv · 1010.5744

Phase diagram of the Hubbard model on honeycomb lattice

Abolhassan Vaezi·Xiao-Gang Wen
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Abstract

In this paper we generalized the slave-particle technique to study the phase diagram of the Hubbard model on honeycomb lattice which may contain charge fluctuations. For large $U$, we have antiferromagnetic order phase. As we decrease $U$ below $U_{c2}\simeq 3t$, the system undergoes a first order phase transition into a gapped spin rotation invariant phase. Under a semiclassical approximation of the slave-particle approach, we find that such phase breaks the translation symmetry, the parity and the lattice rotation symmetry. However, beyond the semiclassical approximation, a $Z_2$ spin liquid that does not break any lattice symmetry is also possible.

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Abolhassan Vaezi, Xiao-Gang Wen. 2010-10-27. Phase diagram of the Hubbard model on honeycomb lattice. https://arxiv.org/abs/1010.5744

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