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arXiv · 0910.2070

Quantum spin liquid with fermionized pi-vortices

Su-Peng Kou·Lan-Feng Liu·Jing He·Ya-Jie Wu
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Abstract

In this paper, we study the non-magnetic insulator state near Mott transition of 2D pi-flux Hubbard model on square lattice and find that such non-magnetic insulator state is quantum spin liquid state with nodal fermionic excitations - nodal spin liquid (NSL). When there exists small easy-plane anisotropic energy, the ground state becomes Z2 topological spin liquid (TSL) with full gapped excitations. The U(1)times U(1) mutual--Chern-Simons (MCS) theory is obtained to describe the low energy physics of NSL and TSL.

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Su-Peng Kou, Lan-Feng Liu, Jing He, Ya-Jie Wu. 2009-10-12. Quantum spin liquid with fermionized pi-vortices. https://arxiv.org/abs/0910.2070

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