Theoretical seminar | 23 March 2022

Prof. Gennady Shvets
Cornell University
Topological photonics across temporal and spatial scales: from higher-order to non-Hermitian

Topological photonics enables unusual and robust properties of electromagnetic waves, including reflections-free photon propagation along strongly curved interfaces and localization at the corners and other discontinuities of photonic structures. Of particular interest are the so-called photonic higher-order topological insulators (PHOTIs) enabling light localization at their corners. I will discuss several examples of the PHOTIs based on topological crystalline insulators emulating spin-orbit coupling. New topological spin-related phases will be discussed, as well as emergence of spin-polarized corner charges, and photonic realizations of such spin-PHOTIs. Finally, theoretical prediction of non-local corner states in non-Hermitian HOTIs and the discovery of the importance of defective Hamiltonians in such systems will be discussed.

PRL 128, 026801 (2022)
PRB 104, 195437 (2021)
Adv. Phot. 2, 046603 (2020)