<8/1(Wed.) 4:00pm>Band Topology in Nodal Line Semimetals with Z2 Monopole Charges
- 2018-07-24
The Solid State Electronic Structure Calculation Lab invites Jun-Young Ahn, a doctoral student of department of physics at Seoul National University and holds a seminar as follows.
Please join us next Wednesday at the seminar.
○ Date: August 1st (Wed), pm 4:00
○ Place: Natural Science 1, Department of Physics Seminar room (#31355)
○ Guest Speaker: Junyeong Ahn (Center for Theoretical Physics, Seoul National University)
○ Title: Band Topology in Nodal Line Semimetals with Z2 Monopole Charges
○ Abstract: Since the discovery of topological insulators and semimetals, there have been many efforts to classify and characterize topological phases of matters. In recent years, three concepts have emerged to become new trends in this direction: fragile topology, higher-order topology, and gap-closing objects (nodes) with multiple topological charges. In this seminar, I will talk about those new concepts based on my recent work on nodal line semimetals hosting nodal lines with two topological charges: one is the well-known pi Berry phase, and the other is the Z2 monopole charge. New analytic methods that I developed for calculating Z2 monopole charges allow systematic studies on this exotic topological charge, which have been difficult up to now. In addition to the theoretical analysis, I will also present a possible material realization based on my colleagues’ first-principles calculations.