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arXiv · 0812.2524

Quantum Non-Magnetic state near Metal-Insulator Transition - a Possible Candidate of Spin Liquid State

Gao-Yong Sun·Su-Peng Kou
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Abstract

In this paper, based on the formulation of an O(3) non-linear sigma model, we study the two-dimensional Pi-flux Hubbard model at half-filling. A quantum non-magnetic insulator is explored near the metal-insulator transition that may be a possible candidate of the spin liquid state. Such quantum non-magnetic insulator on square lattice is not induced by frustrations. Instead, it originates from quantum spin fluctuations with relatively small effective spin moments. In the strong-coupling limit, our results of the spin velocity and spin order parameter agree with results obtained from earlier calculations.

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Gao-Yong Sun, Su-Peng Kou. 2008-12-13. Quantum Non-Magnetic state near Metal-Insulator Transition - a Possible Candidate of Spin Liquid State. https://doi.org/10.1209/0295-5075/87/67002

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