Topological anomalous Floquet photon pump

TL;DR

This paper proposes a simple, experimentally feasible protocol for realizing topological photon pumping mediated by a single qubit, demonstrating non-trivial topological phases and transitions in cavity QED systems.

Contribution

It introduces the anomalous Floquet photon pump, a novel method to achieve topological photon transport using a single qubit in cavity QED.

Findings

Topological phases are achievable over a broad parameter range.

Transitions are driven by frequency-space delocalization.

Topological pumping can be observed via cavity Wigner distribution measurements.

Abstract

There is a close theoretical connection between topological Floquet physics and cavity QED, yet this connection has not been realized experimentally due to complicated cavity QED models that often arise. We propose a simple, experimentally viable protocol to realize non-adiabatic topological photon pumping mediated by a single qubit, which we dub the anomalous Floquet photon pump. For both quantized photons and external drive, the system exhibits a non-trivial topological phase across a broad range of parameter space. Transitions out of the topological phase result from frequency-space delocalization. Finally, we argue that the protocol can be implemented in existing experiments via driven qubit non-linearities, with topological pumping witnessed in measurements of the cavity Wigner distribution functions.