I study many-body quantum systems that are strongly fluctuating. I am particularly interested in systems, where fluctuations give rise to new and exotic phases. Examples include quantum spin liquids (QSL), many-body localised states (MBL) and the Kondo insulator. In QSLs, strong fluctuations induced by local constraints prevent magnetic moments from ordering down to absolute zero. A particularly exciting example is quantum spin ice (see picture on the right), a purported state of matter in some rare-Earth pyrochlores. It is described by a lattice version of Maxwell's theory of light and harbours topological excitations such as magnetic monopoles and fictitious electric charges. Other strongly-fluctuating systems which I have studied include ultracold polar molecules subject to strong disorder, which localises the interacting excitations of the system (many-body localisation) and stops it from thermalising. More recently, I have been looking at how fluctuations of magnetic moments induced by scattering with conduction electrons (Kondo effect) allow the moments to align along the hard-axis, i.e. against the forces from the crystal.

• interplay of Kondo screening, magnetism and superconductivity,
• dynamics of quantum spin liquids at non-zero temperatures,
• thermalisation of many-body quantum systems,
• many-body localisation.

I also welcome enquiries with your own project suggestions.