Spin transport in Aharonov-Bohm ring with exchange interaction

TL;DR

This paper studies how spin-dependent conductance oscillates in a quantum Aharonov-Bohm ring with localized electrons, revealing that the oscillation amplitude depends on the localized spin and aligns with fractional conductance quantization.

Contribution

It provides a theoretical analysis of spin-dependent conductance oscillations in an Aharonov-Bohm ring considering exchange interactions, extending previous fractional quantization concepts.

Findings

Oscillation amplitude is governed by the non-compensated localized spin.

Conductance oscillations depend on chemical potential and magnetic field.

Results support the fractional quantization of ballistic conductance.

Abstract

We investigate spin-dependent conductance through a quantum Aharonov-Bohm ring containing localized electrons which interact with the propagating flow of electrons via exchange interaction of the ferromagnetic or antiferromagnetic type. We analyze the conductance oscillations as a function of both the chemical potential determined by the concentration of the carriers and external magnetic field. It is demonstrated that the amplitude of the conductance oscillations in the ballistic regime is governed by the value of the non-compensated spin localized in the ring. The results are in agreement with the concept of fractional quantization of the ballistic conductance, proposed by us earlier [Phys. Rev. B 71,113311 (2005)].