Spin Precession and Oscillations in Mesoscopic Systems

TL;DR

This paper compares quantum and classical magneto-transport oscillations in mesoscopic systems, highlighting how electron phase coherence affects spin current behavior and tunneling resonances.

Contribution

It provides a detailed analysis of the differences between quantum and classical spin oscillations in mesoscopic structures, emphasizing the role of phase coherence.

Findings

Classical spin current exhibits strong tunneling resonances due to spin precession.

Quantum case requires proper phase treatment to observe oscillations.

Differences are explained by coherent multiple wave reflections.

Abstract

We compare and contrast magneto-transport oscillations in the fully quantum (single-electron coherent) and classical limits for a simple but illustrative model. In particular, we study the induced magnetization and spin current in a two-terminal double-barrier structure with an applied Zeeman field between the barriers and spin disequilibrium in the contacts. Classically, the spin current shows strong tunneling resonances due to spin precession in the region between the two barriers. However, these oscillations are distinguishable from those in the fully coherent case, for which a proper treatment of the electron phase is required. We explain the differences in terms of the presence or absence of coherent multiple wave reflections.