Superinsulator Phase of Two-Dimensional Superconductors

TL;DR

This study uses quantum Monte Carlo simulations to explore the phase diagram of 2D superconductors, revealing a superinsulating phase characterized by superfluid vortex behavior and nonlinear voltage-current relations, influenced by dissipation.

Contribution

It introduces a phenomenological model with finite-mass vortices and dissipation, demonstrating the existence and properties of a superinsulating phase in 2D superconductors.

Findings

Superinsulating phase exhibits superfluid vortex behavior.

Dissipation shifts the superinsulating phase to higher magnetic fields.

Nonlinear voltage-current law characterizes the superinsulating phase.

Abstract

Using path-integral Quantum Monte Carlo we study the low-temperature phase diagram of a two-dimensional superconductor within a phenomenological model, where vortices have a finite mass and move in a dissipative environment modeled by a Caldeira-Leggett term. The quantum vortex liquid at high magnetic fields exhibits superfluidity and thus corresponds to a {\em superinsulating} phase which is characterized by a nonlinear voltage-current law for an infinite system in the absence of pinning. This superinsulating phase is shifted to higher magnetic fields in the presence of dissipation.