Calculated neutron scattering pattern for the "spin ice" state where spins (magnetic moments) mimic the proton disorder in water ice. The study of spin ice materials such as Ho2Ti2O7 may shed light on the role of competing or frustrated interactions in many areas of condensed matter science. This figure appeared on the front cover of science, highlighting a review Steve Bramwell and Michel Gingras wrote on spin ices.
The discovery and subsequent theoretical and experimental work carried worldwide on spin ice systems is one of the most interesting development in the field of magnetism over the past 10 years. The work done at Waterloo has been crucial in explaining a number of issues about spin ices.