Speaker
Aleksandra Nelson
(UZH)
Description
Despite being predicted more than a decade ago, Hopf insulators still have no realistic candidate material realization. The problem with finding such material is two-fold: Most importantly, the corresponding topological invariant - integer-valued Hopf number - is only defined for a two-band system, while another source of the problem stems from the assumed absence of any symmetry required to protect the Hopf phase. Apart from that, it is also not clear which properties of a Hopf insulator can be measured in order to find candidate compounds from the physical response. In this work, we address these problems and discuss physical aspects that should allow for the search of the Hopf insulator compounds.
Authors
Aleksandra Nelson
(UZH)
Dr
Aris Alexandradinata
(University of Illinois at Urbana-Champaign)
Alexey Soluyanov
(ETH Zurich)
