In topological semimetals, the valence band and conduction band meet at
zero-dimensional nodal points or one-dimensional nodal rings, which are
protected by band topology and symmetries. In this Rapid Communication, we
introduce "nodal-link semimetals", which host linked nodal rings in the
Brillouin zone. We put forward a general recipe based on the Hopf map for
constructing models of nodal-link semimetal. The consequences of nodal ring
linking in the Landau levels and Floquet properties are investigated.Comment: 12 pages, 5 figures, including supplemental material. Published
versio
