Magnetic structure of the promising candidate for three-dimensional artificial spin ice: small angle neutron diffraction and micromagnetic simulations

TL;DR

This study combines small-angle neutron diffraction and micromagnetic simulations to analyze the magnetic structure of three-dimensional artificial spin ice, revealing insights into its magnetization states and the effects of demagnetizing fields.

Contribution

It introduces a novel combined experimental and simulation approach to determine the magnetic states in 3D artificial spin ice structures.

Findings

Good agreement with the spin ice model

Demagnetizing fields influence magnetization process

Vortex states affect magnetization behavior

Abstract

Geometrical frustration arised in spin ices leads to fascinating emergent physical properties. Nowadays there is a wide diversity of the artificial structures, mimicking spin ice at the nanoscale and demonstrating some new effects. Most of the nanoscaled spin ices are two dimensional. Ferromagnetic inverse opal-like structures (IOLS) are among inspiring examples of the three-dimensional system exhibiting spin ice behaviour. However detailed examination of its properties is not straightforward. Experimental technique which is able to unambiguously recover magnetization distribution in 3D mesoscaled structures is lacking. In this work we used an approach based on complementary exploiting of small-angle neutron diffraction technique and micromagnetic simulations. External magnetic field was applied along three main directions of the IOLS mesostructure. Comparison of the calculated and measured data allowed us to determine IOLS magnetic state. The results are in good agreement with the spin ice model. Moreover influence of the demagnetizing field and vortex states on the magnetizing process were revealed. Additionally, we speculate that this approach can be also applied to other 3D magnetic mesostructures.