Dynamical Light-Matter Coupling with Protected Superconducting Oscillators

arXiv:2611.10295v1 Announce Type: new Abstract: Superconducting circuits hosting long-lived bosonic modes are an excellent platform for emulating the dynamics of light and matter and exploiting them for quantum information processing. The space of accessible dynamics is greatly extended by introducing the frequency tunability of artificial atoms, whereby the interactions with the light field of a microwave cavity can be modified on demand. However, using external flux bias to control the frequency of transmons introduces significant losses to coupled cavities, reducing their single-photon lifetimes to a few tens of $\mu$s. These imperfections compromise the usefulness of the bosonic mode, which loses its ability to store and manipulate the quantum information of many-photon states.