Oscillations of the superconducting critical current in Nb-Cu-Ni-Cu-Nb junctions

TL;DR

This paper reports experimental observations of oscillations in the critical supercurrent in Nb-Cu-Ni-Cu-Nb junctions, linking the oscillation period to ferromagnet thickness and theoretical models.

Contribution

It provides experimental evidence of supercurrent oscillations in superconductor-ferromagnet structures and compares findings with theoretical predictions.

Findings

Critical supercurrent oscillates with ferromagnet thickness

Oscillation period matches theoretical calculations

Strong supercurrent decay observed with increased ferromagnet thickness

Abstract

We report on experimental studies of superconductor-ferromagnet layered structures. Strong oscillations of the critical supercurrent were observed with the thickness variation of the ferromagnet. Using known microscopic parameters of Ni, we found reasonable agreement between the period of oscillations and the decay of the measured critical current, and theoretical calculations.