Exchange coupling and current-perpendicular-to-plane giant magneto-resistance of magnetic trilayers. Rigorous results within a tight-binding single-band model

TL;DR

This paper demonstrates a rigorous tight-binding model showing that CPP-GMR oscillations are strongly correlated with exchange coupling oscillations, sharing the same period and oscillating in opposite phases as spacer thickness varies.

Contribution

It provides a rigorous, solvable model linking CPP-GMR oscillations with exchange coupling in magnetic trilayers, highlighting their shared periodicity and phase relationship.

Findings

GMR and exchange coupling share the same oscillation period.

Both phenomena oscillate predominantly in opposite phases.

Oscillations are determined by the spacer Fermi surface.

Abstract

It is shown that the current-perpendicular-to-plane giant magneto-resistance (CPP-GMR) oscillations, in the ballistic regime, are strongly correlated with those of the exchange coupling (J). Both the GMR and J are treated on equal footing within a rigorously solvable tight-binding single-band model. The strong correlation consists in sharing asymptotically the same period, determined by the spacer Fermi surface, and oscillating with varying spacer thickness predominantly in opposite phases.