Slow and stored light based on electromagnetically induced transparency (EIT) in single fluxonium artificial atom

Abstract: 
Electromagnetically induced transparency (EIT) has been demonstrated in the atomic system, artificial atoms, and meta-structures. Previous demonstrations of EIT in superconducting artificial atoms involve coupling to other degrees of freedom such as resonators or other superconducting atoms. In this talk, I will present our design and experiment of the EIT with a single Fluxonium qubit inside a microwave waveguide. Owing to the substantial anharmonicity and tunability of the Fluxonium qubit, we construct a Lambda-type three-level system. In this configuration, the controlling and probing transitions are strongly coupled to the transmission line, safeguarding the transition between |0⟩ and |1⟩ states, and ensuring the Fluxonium qubit is close to the sweet spot. Our observations include the manifestation of EIT, a slowdown of light with a delay time of 217 ns, and photon storage. These results highlight the potential for quantum communication in superconducting circuits.