The Physics of Pair Density Waves

TL;DR

This paper reviews the theoretical and experimental understanding of pair density wave (PDW) superconductors, discussing their macroscopic properties, evidence in cuprates, microscopic theories, and related states in various systems.

Contribution

It provides a comprehensive overview of PDW physics, including recent experimental findings, theoretical models, and the role of PDW as a potential fundamental or competing order.

Findings

Experimental evidence for PDW in cuprates

Discussion of microscopic theories of PDW

Overview of PDW states in cold atoms and unconventional superconductors

Abstract

We review the physics of pair density wave (PDW) superconductors. We begin with a macroscopic description that emphasizes order induced by PDW states, such as charge density wave, and discuss related vestigial states that emerge as a consequence of partial meting of the PDW order. We review and critically discuss the mounting experimental evidence for such PDW order in the cuprate superconductors, the status of the theoretical microscopic description of such order, and the current debate on whether the PDW is a "mother order" or another competing order in the cuprates. In addition, we give an overview of the weak coupling version of PDW order, Fulde-Ferrell-Larkin-Ovchinnikov states, in the context of cold atom systems, unconventional superconductors, and non-centrosymmetric and Weyl materials.