Floating phase in a dissipative Josephson junction array

TL;DR

This paper investigates a unique floating phase in dissipative Josephson junction arrays, where local quantum states can slide past each other despite long-range couplings, revealing a novel type of quantum critical behavior.

Contribution

It introduces the concept of a floating phase in dissipative Josephson junction arrays and characterizes its properties and implications for quantum criticality.

Findings

Identification of a floating phase in Josephson junction arrays

Characterization of the metal-superconductor quantum critical point

Proposal for experimental measurement of the critical behavior

Abstract

We consider dissipative quantum phase transitions in Josephson junction arrays and show that the disordered phase in this extended system can be viewed as an unusual floating phase in which the states of local $(0+1)$-dimensional elements (single Josephson junctions) can slide past each other despite arbitrary range spatial couplings among them. The unusual character of the metal-superconductor quantum critical point can be tested by measurements of the current voltage characteristic. This may be the simplest and most natural example of a floating phase.