The influence of spin-dependent phases of tunneling electrons on the conductance of a point ferromagnet/isolator/superconductor contact

TL;DR

This paper investigates how spin-dependent phases affect electron tunneling and conductance in ferromagnet/insulator/superconductor contacts, revealing differences in Andreev reflection probabilities and calculating conductance and bound states.

Contribution

It introduces a model accounting for spin-dependent tunneling phases and derives expressions for Andreev reflection probabilities and conductance in FIS contacts.

Findings

Andreev reflection probabilities differ for electrons and holes.

Energy levels of Andreev bound states are determined.

Ballistic conductance of FIS contact is calculated.

Abstract

The Andreev reflection probability for a ferromagnet/isolator/superconductor (FIS) contact at the arbitrary spin-dependent amplitudes of the electron waves transmitted through and reflected from the potential barrier is found. It is shown that Andreev reflection probabilities of electron and hole excitations in the FIS contact are different. The energy levels of Andreev bound states are found. The ballistic conductance of the point FIS contact is calculated.