Magnetism is a fascinating phenomenon: it is rooted in relativistic quantum mechanics and yet an integral component of the technologies we use every day. In magnetic insulators, where atomic-scale magnetic dipoles carried by electrons are closely bound to a crystal lattice, novel phases of matter with no classical analogues are possible. Chief among these phases are spin-liquids, in which strong fluctuations of magnetic dipoles preclude conventional magnetic order even for temperatures low compared to the average interaction between spins. Such exotic magnetic matter is of great fundamental interest because it features a wealth of coherence and entanglement phenomena – the hallmarks of the quantum world – and is often amenable to theoretical and computational predictions. In this talk, I will present experimental research that brings together materials chemistry, neutron scattering and computer modeling to understand the magnetic excitations in a range of frustrated oxide compounds with triangular , kagome and pyrochlore lattice structures. My talk will emphasize the importance of neutron scattering instrumentation at large-scale facilities to probe complex materials behavior in which chemical disorder, geometrical frustration and quantum fluctuations interplay to stabilize – or destroy – spin-liquid physics.
The work at Georgia tech is support by the U.S. Department of Energy under award DE-SC-0018660 and the National Science Foundation under award NSF-DMR-1750186.