The Meservey-Tedrov effect in FSF double tunneling junctions

TL;DR

This paper demonstrates that the Meservey-Tedrov effect, which alters the quasiparticle energy spectrum in superconductors, explains conductance jumps in FSF double tunneling junctions under magnetic fields, challenging previous explanations.

Contribution

It reveals that the Meservey-Tedrov effect, not just spin-valve or pair-breaking effects, causes conductance changes in FSF junctions under magnetic fields.

Findings

The conductance jump reverses with bias polarity.

Magnetic field modifies quasiparticle energy spectrum.

Meservey-Tedrov effect accounts for observed conductance changes.

Abstract

Double tunneling junctions of ferromagnet-superconductor-ferromagnet electrodes (FSF) show a jump in the conductance when a parallel magnetic field reverses the magnetization of one of the ferromagnetic electrodes. This change is generally attributed to the spin-valve effect or to pair breaking in the superconductor because of spin accumulation. In this paper it is shown that the Meservey-Tedrov effect causes a similar change in the conductance since the magnetic field changes the energy spectrum of the quasi-particles in the superconductor. A reversal of the bias reverses the sign in the conductance jump.