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Fermi liquid behavior and spin-charge separation in underdoped cuprates

Ching-Kit Chan·Tai-Kai Ng
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Abstract

The Gaussian fluctuations in slave-boson mean-field theory of $t-J$ model is analyzed in this paper in the low-doping regime where the superconducting to normal (pseudo-gap phase) transition is driven by vanishing of bose-condensation amplitude. By eliminating the boson and constraint fields exactly in the linear response regime we show that the Gaussian theory describes a Fermi liquid superconductor where the superconducting to normal transition is actually a spin-charge separation transition characterized by a change of Landau parameter from $F_1>-1$ in the superconducting phase to $F_1=-1$ in the pseudo-gap phase. Consequences of this proposal are discussed.

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Ching-Kit Chan, Tai-Kai Ng. 2006-02-21. Fermi liquid behavior and spin-charge separation in underdoped cuprates. https://arxiv.org/abs/cond-mat/0602479

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