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arXiv · 2106.08709

Topology detection in cavity QED

Beatriz Pérez-González·Álvaro Gómez-León·Gloria Platero
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Abstract

We explore the physics of topological lattice models in c-QED architectures for arbitrary coupling strength, and the use of the cavity transmission as a topological marker. For this, we develop an approach combining the input-output formalism with an expansion in quantum fluctuations which allows to go beyond the small-coupling regime. We apply our formalism to a fermionic Su-Schrieffer-Heeger (SSH) chain coupled to a single-mode cavity, and find that the cavity can indeed act as a quantum sensor for topological phases, where the initial state preparation plays a crutial role. Additionally, we discuss the persistence of topological features as the coupling strength increases, in terms of an effective Hamiltonian, and calculate the entanglement entropy.

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Beatriz Pérez-González, Álvaro Gómez-León, Gloria Platero. 2021-06-16. Topology detection in cavity QED. https://doi.org/10.1039/d2cp01806c

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