Quantum-disordered slave-boson theory of underdoped cuprates

TL;DR

This paper investigates the stability of the spin gap phase in underdoped cuprates using a quantum-disordered slave-boson approach, revealing a connection to the nodal liquid theory and emphasizing the role of quantum fluctuations.

Contribution

It introduces a quantum-disordered slave-boson framework for the t-J model, linking the spin gap phase to quantum criticality and the nodal liquid state in underdoped cuprates.

Findings

Spin gap phase can be stabilized in quantum disordered regimes.

Quantum fluctuations modify gauge field behavior at finite temperatures.

Connection established between quantum disordered bosons and nodal liquid theory.

Abstract

We study the stability of the spin gap phase in the U(1) slave-boson theory of the t-J model in connection to the underdoped cuprates. We approach the spin gap phase from the superconducting state and consider the quantum phase transition of the slave-bosons at zero temperature by introducing vortices in the boson superfluid. At finite temperatures, the properties of the bosons are different from those of the strange metal phase and lead to modified gauge field fluctuations. As a result, the spin gap phase can be stabilized in the quantum critical and quantum disordered regime of the boson system. We also show that the regime of quantum disordered bosons with the paired fermions can be regarded as the strong coupling version of the recently proposed nodal liquid theory.