The significance of "stripes" in the physics of the cuprates, the Hubbard model, and other highly correlated electronic systems

TL;DR

This paper discusses the role of stripe phases as a common and significant feature in the physics of cuprates and Hubbard models, emphasizing their non-weak-coupling origin and competition with superconductivity.

Contribution

It highlights the importance of stripe order in correlated systems, clarifies their non-nesting origin, and reviews their emergence in theoretical and numerical studies.

Findings

Stripes are prevalent in cuprate phase diagrams.

Stripe order often competes with d-wave superconductivity.

Stripe phenomena are not related to Fermi-surface nesting.

Abstract

"Stripes" - meaning unidirectional charge-density-waves, sometimes (but not always) accompanied by spin-density-waves with twice the period - are now known to arise in broad swathes of the cuprate phase diagram, and appear as a strong ordering tendency in numerical studies of Hubbard-like models of highly correlated electron systems. Jan Zaanen's work played a seminal role in predicting their existence, and exploring their possible significance. They are {\it not} related to any weak-coupling physics associated with some form of Fermi-surface nesting. And whether one likes them or not, they are surprisingly difficult to avoid; in the Hubbard model, for example, they often appear as an alternative order that can out-compete the otherwise favored $d$-wave superconductivity.