Spin liquid phase and Higgs transitions in spin ice
Wednesday 08 February 2012
to 10:50 at
Stephen Powell (University of Maryland College Park)
In frustrated systems, where competing interactions disfavour the formation of order, a "spin liquid" can appear at low temperatures. In contrast to conventional magnetic phases, the spin liquid exhibits both strong correlations and large fluctuations. A prominent experimental example is provided by the class of compounds known as "spin ice".
Perturbations applied to such systems can relieve the frustration and cause ordering, and I will argue that the resulting transitions go beyond the standard Landau paradigm. They can instead be understood as Higgs transitions of an emergent gauge theory and belong to a family of new universality classes. I will present theoretical predictions of such unconventional transitions in the spin ice materials, and supporting evidence from numerical simulations.