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arXiv · 1007.2507

Confinement-deconfinement interplay in quantum phases of doped Mott insulators

Abstract

It is generally accepted that doped Mott insulators can be well characterized by the t-J model. In the t-J model, the electron fractionalization is dictated by the phase string effect. We found that in the underdoped regime, the antiferromagnetic and superconducting phases are dual: in the former, holons are confined while spinons are deconfined, and {\it vice versa} in the latter. These two phases are separated by a novel phase, the so-called Bose-insulating phase, where both holons and spinons are deconfined. A pair of Wilson loops was found to constitute a complete set of order parameters determining this zero-temperature phase diagram. The quantum phase transitions between these phases are suggested to be of non-Landau-Ginzburg-Wilson type.

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Peng Ye, Chu-Shun Tian, Xiao-Liang Qi, Zheng-Yu Weng. 2011-03-17. Confinement-deconfinement interplay in quantum phases of doped Mott insulators. https://doi.org/10.1103/physrevlett.106.147002

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