Thursday, October 3, 2013, 3pm
Location: Room 1110 of the Nguyen Engineering Building

Indu Satija
School of Physics, Astronomy, and Computational Sciences
George Mason University

Quasicrystals: A Different Type of Ordered States of Matter with Non-Trivial Topology

Abstract

Quasicrystal is a structure that is ordered but not periodic. Following its discovery in 1982, which was honored with a Nobel prize in 2011, the International Union of Crystallography changed the definition of a crystal in 1992, retaining only the criterion of an essentially sharp diffraction pattern. Starting with the nobel discovery, this talk will provide historical perspective on the subject that will also include aperiodic tiles decorating medieval mosques predating 12th century and fascinating Penrose tiles of mathematical physicist Roger Penrose invented in 1974. We will discuss recent studies that suggest that quasicrystals describe topologically nontrivial states of matter like quantum Hall states. These characteristics will be elucidated using simple examples that will also include superconducting wires where the topology is found to have direct influence on the Majorana modes.