Title: Topological boundary invariants for Floquet systems and quantum walks,
Abstract: A Floquet systems is a periodically driven quantum system. It can be
described by a Floquet operator. If this unitary operator has a gap in the
spectrum, then one can define associated topological bulk invariants which can
either only depend on the bands of the Floquet operator or also on the time as
a variable. It is shown how a K-theoretic result combined with the
bulk-boundary correspondence leads to edge invariants for the half-space
Floquet operators. These results also apply to topological quantum walks.