Université de Montréal - Pavillon J.-Armand-Bombardier
Jeffrey Quilliam, Département de Physique, Université de Sherbrooke, Sherbrooke, QC, Canada
For many years, physicists have searched for the elusive quantum spin liquid (QSL) state – a disordered, long-range entangled ground state of a magnetic material induced by quantum fluctuations and frustration. Most often, this search has concentrated on highly frustrated lattices, such as the kagome lattice, and on spin-1/2 materials. However, here I will present two new avenues for the discovery of QSL states. In one case, orbital degrees of freedom appear to play a crucial role in an otherwise frustration-free honeycomb lattice. In the second case, spin-1 moments appear to be essential to generating a spin liquid ground state on a triangular lattice. Specifically, I will present local-probe measurements, µSR and NMR, on these materials, measurements that allow us to separate intrinsic magnetic properties from impurity effects and to probe the basic spin excitations out of these apparent spin liquid ground states.
Site web du groupe du Prof. Quilliam
Cette conférence est présentée par le RQMP Versant Nord du Département de physique de l'Université de Montréal et le Département de génie physique de Polytechnique Montréal.