Conductance Quantization and Magnetoresistance in Magnetic Point Contacts

TL;DR

This paper theoretically investigates electron transport in magnetic point contacts, focusing on how atomic-scale domain walls influence conductance quantization and magnetoresistance, revealing orientation-dependent conductance sequences and oscillatory magnetoresistance effects.

Contribution

It introduces a theoretical model analyzing the impact of atomic-scale domain walls on conductance quantization and magnetoresistance in magnetic point contacts.

Findings

Conductance quantization depends on magnetization orientation.

Magnetoresistance is significantly enhanced in narrow contacts.

Magnetoresistance oscillates with conductance.

Abstract

We theoretically study the electron transport through a magnetic point contact (PC) with special attention to the effect of an atomic scale domain wall (DW). The spin precession of a conduction electron is forbidden in such an atomic scale DW and the sequence of quantized conductances depends on the relative orientation of magnetizations between left and right electrodes. The magnetoresistance is strongly enhanced for the narrow PC and oscillates with the conductance.