Topology detection in cavity QED

Beatriz Pérez-González, Álvaro Gómez-León, Gloria Platero

Published 2021-06-16Version 1

We explore the physics of topological lattices models in c-QED architectures for different coupling strengths. For this, we develop an approach combining the input-output formalism with Mean Field theory, which includes self-consistency and quantum fluctuations to first order. We apply our method to the case of a fermionic Su-Schrieffer-Heeger (SSH) chain and discuss the possibility to use the cavity transmission as a topological marker. We find that this is possible for a wide range of coupling strengths and that the initial state of the chain can have an important impact. In addition, we discuss the persistence of topological features when the coupling strength increases, in terms of an effective Hamiltonian, and calculate the entanglement entropy. Our approach can be applied to other fermionic systems, opening a route to the characterization of their topological properties.