Synthetic gauge fields and homodyne transmission in Jaynes-Cummings lattices

TL;DR

This paper explores how synthetic gauge fields in Jaynes-Cummings lattices influence photon dynamics, revealing degeneracies and strong correlations, and analyzes homodyne transmission to identify interaction effects beyond linear response.

Contribution

It derives photon hopping amplitudes in circuit QED arrays and demonstrates how synthetic gauge fields induce degeneracies and correlations in Jaynes-Cummings lattices.

Findings

Degeneracies in the single-excitation spectrum emerge under synthetic gauge fields.

Homodyne transmission reveals signatures of photon interactions beyond linear response.

Photon hopping amplitudes are quantitatively characterized in circuit QED arrays.

Abstract

Many-body physics is traditionally concerned with systems of interacting massive particles. Recent studies of effective interactions between photons, induced in the circuit QED architecture by coupling the microwave field to superconducting qubits, have paved the way for photon-based many-body physics. We derive the magnitude and intrinsic signs of photon hopping amplitudes in such circuit QED arrays. For a finite, ring-shaped Jaynes-Cummings lattice exposed to a synthetic gauge field we show that degeneracies in the single-excitation spectrum emerge, which can give rise to strong correlations for the interacting system with multiple excitations. We calculate the homodyne transmission for such a device, explain the generalization of vacuum Rabi splittings known for the single-site Jaynes-Cummings model, and identify fingerprints of interactions beyond the linear response regime.