Emergent quasi-particles in frustrated magnets

Crystalline solids with Interacting local moments that do not fully
order at low temperatures can support a variety of strongly correlated
electronic phenomena. With no static magnetism or symmetry breaking,
the quantum spin liquid (QSL) represents an important albeit rare
limit [1]. A much larger variety of materials has been found to have
spin liquid like properties in restricted temperature and frequency
regimes. I shall describe experiments that explore such materials by
scattering neutrons from their emergent magnetic quasi-particles. The
materials range from insulating rare earth oxides through transition
metal oxides near the metal insulator transition to Kondo semi-metals
and heavy fermions systems. Conducted using the latest neutron
scattering instrumentation, the experiments offer detailed atomic
scale insights into strongly correlated phenomena that challenge
conventional understanding of magnetism in solids.

[1] C. Broholm, R. J. Cava, S. A. Kivelson, D. G. Nocera, M. R.
Norman, and T. Senthil, Science, Vol. 367, Issue 6475, (2020)