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 …

Micromagnetics has been the method of choice to interpret experimental data in the area of
microscopic magnetism for several decades. In this article, we show how progress has been …

Magnetic monopoles have been predicted to occur as emergent fractional quasiparticles
inside pyrochlore spin ice, a frustrated magnetic insulator. Experimental signatures of such …

Free monopoles have fascinated and eluded researchers since their prediction by Dirac in
1931. In spin ice, the bulk frustrated magnet, local ordering principles known as ice rules …

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 …

Magnetic monopoles, proposed as elementary particles that act as isolated magnetic south
and north poles, have long attracted research interest as magnetic analogs to electric …

Recent advances in nanotechnology allow model systems to be constructed, in which
frustrated interactions can be tuned at will, such as artificial spin ice. The symmetry of the …

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 …

We analyze an array of linearly extended monodomain dipoles forming square and kagome
lattices. We find that its phase diagram contains two (distinct) finite-entropy kagome ice …

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 …