Frustration, the presence of competing interactions, is ubiquitous in the physical sciences
and is a source of degeneracy and disorder, which in turn gives rise to new and interesting …

Lithographic processing and film growth technologies are continuing to advance, so that it is
now possible to create patterned ferroic materials consisting of arrays of sub-1 μm elements …

Artificial spin ice is a class of lithographically created arrays of interacting ferromagnetic
nanometre-scale islands. It was introduced to investigate many-body phenomena related to …

We study the thermal relaxation of artificial spin ice with photoemission electron microscopy,
and are able to directly observe how such a system finds its way from an energetically …

A Skyrmion crystal typically arises from helical spin structures induced by the Dzyaloshinskii-
Moriya interaction. Experimentally its physical exploration has been impeded because it is a …

Based on a linearized Landau-Lifshitz equation, we show that two-dimensional periodic
allay of ferromagnetic particles coupled with magnetic dipole-dipole interactions supports …

Two-dimensional artificial spin-ice systems constructed from arrays of dipolar coupled
monodomain magnets offer an experimental route to study the physics of frustration and a …

Arrays of suitably patterned and arranged magnetic elements may display artificial spin-ice
structures with topological defects in the magnetization, such as Dirac monopoles and Dirac …

In 1935, Pauling estimated the residual entropy of water ice with remarkable accuracy by
considering the degeneracy of the ice rule solely at the vertex level. Indeed, his estimate …

We present a methodology to explore experimentally the formation of thermally induced long-
range ground-state ordering in artificial spin-ice systems. Our novel approach is based on …