Dissipation-driven superconductor-insulator transition in linear arrays of Josephson junctions capacitively coupled to metallic films

TL;DR

This paper investigates how a proximate diffusive metal influences the superconductor-insulator transition in linear Josephson-junction arrays, revealing a dissipation-driven transition with observable signatures in low-temperature transport properties.

Contribution

It introduces a theoretical model showing how dynamic Coulomb screening stabilizes an insulating state and drives a superconductor-insulator transition in Josephson arrays.

Findings

Backscattering stabilizes the insulating ground state.

Resistivity exhibits clear signatures of the transition.

Transport properties change markedly near the critical point.

Abstract

We study the low-temperature properties of linear Josephson-junction arrays capacitively coupled to a proximate two-dimensional diffusive metal. Using bosonization techniques, we derive an effective model for the array and obtain its critical properties and phases at T = 0 using a renormalization group analysis and a variational approach. While static screening effects given by the presence of the metal can be absorbed in a renormalization of the parameters of the array, backscattering originated in the dynamically screened Coulomb interaction produces a non-trivial stabilization of the insulating groundstate and can drive a superconductor-insulator transition. We study the consequences for the transport properties in the low-temperature regime. In particular, we calculate the resisitivity as a function of the temperature and the parameters of the array, and obtain clear signatures of a superconductor-insulator transition that could be observed in experiments.