Abstract

One of the most successful branches of physics where manifestly quantum-mechanical phenomena can be seen is "cavity quantum electrodynamics (cavity QED)". Cavity QED is an archetypal quantum hybrid system where an atom interacting predominantly with a single electromagnetic mode. The idea has been evolved to the extent that the constituent single electromagnetic mode can be any "harmonic oscillator (HO)" and the atom can be any "two-level system (TLS) or anharmonic oscillator". The famous examples of the ramification are ion trap system in the Lamb-Dicke regime where ion's internal degree of freedom (TLS) interacting with its center of mass motion (HO), and superconducting-circuit QED where a superconducting qubit (TLS) interacting with a microwave resonator mode (HO). We are exploring further frontier of this wonderful realm of "meta-cavity QED" to make impossible possible and put forward the idea that a superconducting qubit (TLS) can strongly interact with a ferromagnetic magnon mode (HO). I will report our recent experimental results on the meta-cavity QED system and discuss the tantalizing possibility of addressing superconducting qubits by optical photons.