Enhanced Josephson tunneling between high temperature superconductors through a normal pseudogap underdoped cuprate with a finite energy cooperon

TL;DR

This paper investigates how a pseudogap underdoped cuprate spacer enhances Josephson tunneling between high-temperature superconductors, highlighting the role of finite energy cooperon excitations in the process.

Contribution

It introduces a model explaining the enhanced Josephson coupling through a pseudogap barrier, emphasizing the contribution of cooperon excitations alongside nodal quasiparticles.

Findings

Cooperon excitations significantly enhance Josephson coupling.

The YRZ model accurately describes temperature dependence of the coupling.

Enhanced tunneling is comparable from cooperons and nodal quasiparticles.

Abstract

The Josephson coupling between optimally cuprate superconductors separated by a spacer with a finite energy cooperon excitation which contributes to the Josephson coupling strength, is examined. For an underdoped cuprate barrier in its normal state, the YRZ model gives a good description of the temperature dependent enhanced Josephson coupling. A detailed examination of origin of the enhancement shows a significant contribution from the cooperon excitation which is comparable to that from nodal quasiparticles.