Charge ordering of magnetic monopoles in triangular spin ice patterns

TL;DR

This study explores how magnetic monopoles in artificial spin ice on a honeycomb lattice exhibit charge order without spin order, revealing complex magnetic behaviors under applied fields.

Contribution

It demonstrates magnetic charge ordering in honeycomb spin ice patterns without accompanying spin order, using magnetic force microscopy to analyze field-dependent behaviors.

Findings

Maximum charge order of magnetic monopoles at coercivity

Charge order occurs without spin order

Magnetic frustration peaks at coercivity

Abstract

Artificial spin ice offers the possibility to investigate a variety of dipolar orderings, spin frustrations and ground states. However, the most fascinating aspect is the realization that magnetic charge order can be established without spin order. We have investigated magnetic dipoles arranged on a honeycomb lattice as a function of applied field, using magnetic force microscopy. For the easy direction with the field parallel to one of the three dipole sublattices we observe at coercivity a maximum of spin frustration and simultaneously a maximum of charge order of magnetic monopoles with alternating charges $\pm$ 3.