Anomalous Metallic Phase in Tunable Destructive Superconductors

TL;DR

This paper studies the destructive superconductivity in InAs nanowires with Al shells, revealing an anomalous metallic phase with temperature-independent resistance controlled by magnetic fields, supported by mean-field theory.

Contribution

It demonstrates the existence of an anomalous metallic phase in tunable destructive superconductors, expanding understanding of quantum phase transitions in nanoscale systems.

Findings

Excellent agreement with mean-field theory across multiple reentrant transitions

Observation of an anomalous metal phase with temperature-independent resistance

Control of resistance over two orders of magnitude by a small magnetic field

Abstract

Multiply connected superconductors smaller than the coherence length show destructive superconductivity, characterized by reentrant quantum phase transitions driven by magnetic flux. We investigate the dependence of destructive superconductivity on flux, transverse magnetic field, temperature, and current in InAs nanowires with a surrounding epitaxial Al shell, finding excellent agreement with mean-field theory across multiple reentrant transitions. Near the crossover between destructive and nondestructive regimes, an anomalous metal phase is observed with temperature-independent resistance, controlled over two orders of magnitude by a millitesla-scale transverse magnetic field.