Quantized Corner Charge, Topological Pumps and the 2nd Chern Number
February 3rd, 2020 IOANNIS PETRIDES Eidgenössische Technische Hochschule Zürich

Topological insulators are a novel state of matter that share a common feature: their spectral bands are associated with a nonlocal integer-valued index, commonly manifesting through quantized bulk phenomena and robust boundary effects. In this talk, we show using dimensional reduction that second-order topological insulators are descendants from a chiral semimetal in four dimensions. Within this approach, the quantization of the charge accumulation at the corners of the 2D descendants is obtained and related to the topological index - the 2nd Chern number - of the ancestor model. As an extension, we provide a connection between the boundary states of second-order topological insulators and topological pumps; the latter being dynamical realizations of high-dimensional Chern insulators.

Seminar, February 3, 2020, 10:15. ICFO’s Seminar Room

Hosted by Prof. Maciej Lewenstein