Topological pumping in acoustic Fock lattices

Topological pumping, as an efficient form of energy transfer protected by nontrivial topology, has been intensively studied in condensed matter physics and optics. Conventional topological pumping schemes are mainly related to edge states. In this work, we realize a topological pumping based on Fock lattices for acoustic waves. The acoustic Fock lattice supports defect states that are protected by nearly constant band gaps throughout the modulation process, which enables a high pumping efficiency. We experimentally verify the existence of the topological pumping in acoustic Fock lattices and, moreover, demonstrate an acoustic beam focusing as a potential application. Our results pave the way for more efficient adiabatic topological propagations, which can be extended to other systems.