Science Daily April 2, 2018
In artificial spin ice, which in certain phases appears disordered, the material is ordered, but in a “topological” form. A team of researchers in the US (University of Illinois at Urbana-Champaign, Los Alamos National Laboratory, University of Illinois at Urbana-Champaign, Lawrence Berkeley National Laboratory, University of Minnesota, Yale University) explored a particular artificial spin ice geometry, called Shakti spin ice which could reach its low-energy state as temperature was reduced in successive quenches. Shakti spin ice stubbornly remained at about the same energy level that could be mapped exactly into the “dimer cover model,” whose topological properties had been recognized before. The data from the experiment confirmed topological charge conservation and thus a long lifetime for the excitations. Findings open the door to a wide range of possible new studies… read more. Open Access TECHNICAL ARTICLE
Scanning electron microscopy image showing the structure of the Shakti artificial spin ice lattice. Credit: Nature Physics 2018