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arXiv · 0804.3435

Fluctuation Effect in the π-flux State for Undoped High-Temperature Superconductors

T. Morinari
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Abstract

The effect of fluctuations about the pi-flux mean field state for the undoped high-temperature superconductors is investigated. It is shown that fluctuations of the mean fields lead to a self-energy correction that doubles the band width of the fermion dispersion in the lowest order. The dynamical mass generation is associated with the self-energy effect due to the interaction mediated by the Lagrange multiplier field, which is introduced to impose the constraint on the fermions. A self-consistent picture about the mass generation and the prop- agation of the Lagrange multiplier field without damping is proposed. The antiferromagnetic long-range ordering is described without introducing an additional repulsive interaction. The theory suggests a natural framework to study spin disordered systems in which fermionic excitations are low-lying excitations.

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T. Morinari. 2008-12-03. Fluctuation Effect in the π-flux State for Undoped High-Temperature Superconductors. https://doi.org/10.1143/jpsj.77.114708

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