Theory of magnetotransport in artificial kagome spin ice

TL;DR

This paper introduces a circuit model for understanding magnetotransport in artificial kagome spin ice, linking spin correlations to Hall voltage and revealing enhanced signals during magnetic-charge ordering transitions.

Contribution

It presents a novel resistor network model that connects local magnetization rules to measurable Hall voltages in artificial kagome spin ice systems.

Findings

Hall voltage relates to spin correlations.

Hall signal increases during magnetic-charge ordering.

Model can be applied to design magnetoresistance devices.

Abstract

Magnetic nanoarray with special geometries exhibits nontrivial collective behaviors similar to those observed in the spin ice materials. Here we present a novel circuit model to describe the complex magnetotransport phenomena in artificial kagome spin ice. In this picture, the system can be viewed as a resistor network driven by voltage sources that are located at vertices of the honeycomb array. The differential voltages across different terminals of these sources are related to the ice-rules that govern the local magnetization ordering. The circuit model relates the transverse Hall voltage of kagome ice to the underlying spin correlations. Treating the magnetic nanoarray as metamaterials, we present a mesoscopic constitutive equation relating the Hall resistance to magnetization components of the system. We further show that the Hall signal is significantly enhanced when the kagome ice undergoes a magnetic-charge ordering transition. Our analysis can be readily generalized to other lattice geometry, providing a quantitative method for the design of magnetoresistance devices based on artificial spin ices.