[Seminar] "Experimental investigation of quantum spin liquids" by Prof. Bella Lake

Unlike conventional magnets where the magnetic moments are partially or completely static in the ground state, in a quantum spin liquid they remain in collective motion down to the lowest temperatures. The importance of this state is that it is coherent and highly entangled without breaking local symmetries. The spin liquid state is expected to occur in highly frustrated magnets such as those consisting or triangular and tetrahedral arrangements of magnetic ions. This state is however very rare with only a few Hamiltonians known theoretically to support it and only a few experimental realizations in existence. This talk will discuss the discovery and investigation of two new compounds displaying spin liquid behavior. These compounds have two- and three-dimensional lattices respectively, and their magnetic Hamiltonians have never been investigated either experimentally or theoretically prior to this work. Neutron scattering and physical properties data will be presented alongside theoretical calculations which together provide strong evidence for the spin liquid state.