Coherent Superconductivity with a Large Gap Ratio from Incoherent Metals

Aavishkar A. Patel, Michael J. Lawler, Eun Ah Kim

Research output: Contribution to journalArticlepeer-review

33 Scopus citations

Abstract

A mysterious incoherent metallic (IM) normal state with T-linear resistivity is ubiquitous among strongly correlated superconductors. Recent progress with microscopic models exhibiting IM transport has presented the opportunity for us to study new models that exhibit direct transitions into a superconducting state out of IM states within the framework of connected Sachdev-Ye-Kitaev "quantum dots." Here, local Sachdev-Ye-Kitaev interactions within a dot produce IM transport in the normal state, while local attractive interactions drive superconductivity. Through explicit calculations, we find two features of superconductivity arising from an IM normal state. First, despite the absence of quasiparticles in the normal state, the superconducting state still exhibits coherent superfluid transport. Second, the nonquasiparticle nature of the IM Green's functions produces a large enhancement in the ratio of the zero-temperature superconducting gap Δ and transition temperature TSC, 2Δ/TSC, with respect to its BCS value of 3.53.

Original languageEnglish
Article number187001
JournalPhysical Review Letters
Volume121
Issue number18
DOIs
StatePublished - 30 Oct 2018

Bibliographical note

Publisher Copyright:
© 2018 American Physical Society.

Fingerprint

Dive into the research topics of 'Coherent Superconductivity with a Large Gap Ratio from Incoherent Metals'. Together they form a unique fingerprint.

Cite this