Physics Colloquium: Fascinating aperiodic crystals

Abstract: 

For more than a century the understanding of physical and chemical properties of solids has been based on the notion of periodicity in a crystal, associated with long-range order.  The discovery, in a wide range of systems, of solids with long-range order yet without translational periodicity at least in one dimension led to a new definition of crystals.   This new class of ordered structure is named aperiodic crystals and encompass incommensurately modulated phases, incommensurate composites and quasicrystals. This opened a completely new field of research where the understanding of the atomic structure and associated physical and chemical properties has to be reconsidered with new perspectives.

This lecture will provide with an introduction to the fascinating field of aperiodic crystals focussing on icosahedral quasicrystals. I will present results going from the detailed understanding of the atomic structure to some of their physical properties. This field is a nice example where the interplay between the development of experimental techniques and advances in the theory has been crucial. 
 

Event Organizer: Prof. Amiel Sternberg