Cuprates as doped U(1) spin liquids

TL;DR

This paper proposes that underdoped cuprates can be understood as doped U(1) spin liquids, linking Mott insulator physics with superconductivity and suggesting experimental signatures of conserved gauge flux.

Contribution

It introduces a theoretical framework connecting U(1) spin liquids with cuprate phenomenology, emphasizing the role of a conserved gauge flux near the Mott transition.

Findings

Universal physics of Mott transition applies to underdoped cuprates.

Emergence of conserved gauge flux characterizes deconfinement in U(1) spin liquids.

Proposals for experiments to detect gauge flux in cuprates.

Abstract

We explore theoretically the notion that the underdoped cuprates may be viewed as doped U(1) spin liquid Mott insulators. We pursue a conceptually clear version of this idea that naturally incorporates several aspects of the phenomenology of the cuprates. We argue that the low doping region may be fruitfully discussed in terms of the universal physics associated with a chemical potential tuned Mott transition between a U(1) spin liquid insulator and a d-wave superconductor. A precise characterization of the deconfinement in the U(1) spin liquid is provided by the emergence of a conserved gauge flux. This extra conservation law should hold at least approximately in the underdoped materials. Experiments that could possibly detect this conserved gauge flux are proposed.