Physics Seminar
Low dimensional and topological states in the presence of disorder
Speaker: Tom Lancaster (Durham University)
Date: Wednesday 19 January 2022
Time: 15:00
Venue: Zoom
Low-dimensional quantum magnetism continues to be of great theoretical and experimental interest, as reduced dimensionality supports strong quantum fluctuations that can result in novel excitations and critical behaviour. Of particular recent importance is understanding physics in reduced dimensions using notions from topology. Examples include topological objects such as walls, vortices and skyrmions, which exist in the spin textures of a range of magnetic systems, and one-dimensional spin chain systems, where topological considerations are key in elucidating the possible ground states and excitation spectra. Here we discuss our recent results in this area including the controlled introduction of disorder into (i) a two dimensional molecular series and (ii) a skyrmion material. We emphasise the use of muon-spin relaxation as a sensitive probe of emergent magnetism in these systems, since muons have repeatedly been shown to be sensitive to long-range magnetic order in two and one dimensions which is often very difficult to observe using other techniques, and also to low-energy dynamics.