Fermi liquid behavior and spin-charge separation in underdoped cuprates

TL;DR

This paper analyzes Gaussian fluctuations in the slave-boson mean-field theory of the t-J model, revealing a spin-charge separation transition in underdoped cuprates characterized by a change in Landau parameters.

Contribution

It introduces a Gaussian fluctuation framework that describes a spin-charge separation transition in underdoped cuprates within the t-J model.

Findings

Identifies a transition from Fermi liquid to spin-charge separated phase.

Shows the superconducting to pseudo-gap transition involves a change in Landau parameter.

Describes the low-doping regime behavior of cuprates.

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.