Superconductor-insulator transition in nanowires and nanowire arrays

TL;DR

This paper explores the superconductor-insulator transition in nanowires and arrays, focusing on quantum phase-slip effects and how magnetic frustration influences the transition, with implications for quantum device design.

Contribution

It analyzes the crossover behavior between superconducting and capacitive responses in nanowires and predicts quantum phase transitions in nanowire arrays tuned by magnetic frustration.

Findings

Crossover from superconducting to capacitive response depending on ES/EL ratio.

Quantum phase transitions in nanowire arrays as a function of magnetic frustration.

Comparison with experimental results on quantum phase-slip phenomena.

Abstract

Superconducting nanowires are the dual elements to Josephson junctions, with quantum phase-slip processes replacing the tunneling of Cooper pairs. When the quantum phase-slip amplitude ES is much smaller than the inductive energy EL, the nanowire responds as a superconducting inductor. When the inductive energy is small, the response is capacitive. The crossover at low temperatures as a function of ES/EL is discussed and compared with earlier experimental results. For one-dimensional and two-dimensional arrays of nanowires quantum phase transitions are expected as a function of ES/EL. They can be tuned by a homogeneous magnetic frustration.