Physics Colloquium: Real-space and reciprocal-space topology in solid-state matters.
Gen Yin, UCLA
Abstract: One of the most exciting developments in solid-state materials is the recognition of topology in quantized phenomena. Topology is a mathematical concept designed to classify shapes. Such classification is usually labeled by certain integer numbers that cannot vanish under smooth transformations. Borrowing this concept, physicists recognized that the Landau levels in integer quantum Hall effect are fundamentally determined by the topology of the Bloch states living in k-space. This understanding had led to many exciting discoveries including quantum spin Hall effect (Z2 order), quantum anomalous Hall effect, topological insulators, Weyl semimetals, and topological superconductors. Similarly, a real-space topological object can also be found in solid-state matters: magnetic skyrmions. These discoveries had opened up many exciting possibilities that are useful both for fundamental understanding and device applications. In this presentation I will review the basic idea of topological classification of materials in real and reciprocal spaces. Experimental means to manipulate the topological phases will be discussed in detail.
Thursday, February 20 at 3:15pm
Regents Hall, 109
3700 O St. NW