Seminar - Physics Department

Line-graph-lattice models and materials

Dr. Christie Chiu, Princeton University

Thursday, October 28, 2021: 11:30am
LGRT 1033

Category: Condensed Matter Seminar

The geometric properties of a lattice can have profound consequences on its band spectrum. For example, geometric frustration and symmetry constraints can give rise to dispersionless and topologically nontrivial bands, respectively. Line-graph lattices have been known to exhibit the former; in this talk, I will discuss how we have shown that line-graph-lattice flat bands may also exhibit the latter and host fragile topology [1]. Given that line-graph lattices arise naturally from lattices of microwave resonators, this theoretical work informs experimental studies with superconducting circuits. At the same time, line-graph lattices may be present within real materials. I will also discuss how this possibility has motivated a high-throughput search for line-graph-lattice crystalline structures within a database of inorganic stoichiometric materials [2].

[1] C. S. Chiu et al. Fragile Topology in Line-Graph Lattices with 2, 3, or 4 Gapped Flat Bands. Physical Review Research 2, 043414 (2020).

[2] C. S. Chiu, et al. Line-graph-lattice crystal structures of stoichiometric materials. arXiv: 2109.12897 (2021).

View this event on the Physics Department website