Department of Physics Bldg., Voutes, 3rd floor Seminar Room
Time
16:00
Language
English
Abstract
Magnetism manifests itself through the collective interaction of atomic magnetic moments; as that, it is a highly temperature and volume dependent quantum mechanical phenomenon. In this framework the different length scales straddling nanoscale to bulk materials' regimes offer a rich playground for tailoring microscopic physical parameters and interaction pathways. We explain that crystal structure, when perturbed by chemical functionalisation or external stimuli (pressure, light, temperature), is a key feature for understanding and exploiting the interplay among different electronic degrees of freedom, namely, spin-charge-lattice. Examples are drawn from bulk solid-state compounds, where unusual phase transitions are driven by the frustrated topology of the lattice. In the other extreme, concerned with colloidal nanocrystals in various topological configurations, size and shape effects promote electronic confinement but benefit mutlifunctionality. The observed phenomena and their technological perspectives are highlighted; selected materials' advances involve superparamagnetism (MRI contrast enhancers), photonic crystal like behavior (optical switching), magnetoelectricity and exchange bias (data storage).
