Quantum phase slips in superconducting Nb nanowire networks deposited on self-assembled Si templates

TL;DR

This paper investigates quantum phase slips in superconducting Nb nanowire networks on silicon templates, revealing the influence of thermal and quantum fluctuations on their electrical resistance.

Contribution

It demonstrates the fabrication of interconnected Nb nanowire networks on porous silicon and analyzes their phase slip behavior using models for thermal and quantum fluctuations.

Findings

Nanowire networks show nonzero resistance below critical temperature.

Transport data align with models of thermal and quantum phase slips.

Nanowires are polycrystalline with ~10 nm grain size.

Abstract

Robust porous silicon substrates were employed for generating interconnected networks of superconducting ultrathin Nb nanowires. Scanning electron microscopy analysis was performed to investigate the morphology of the samples, which constitute of polycrystalline single wires with grain size of about 10 nm. The samples exhibit nonzero resistance over a broad temperature range below the critical temperature, fingerprint of phase slippage processes. The transport data are satisfactory reproduced by models describing both thermal and quantum fluctuations of the superconducting order parameter in thin homogeneous superconducting wires.