Circuit Quantum Electrodynamics with a Superconducting Quantum Point   Contact
  We consider a superconducting quantum point contact in a circuit quantum electrodynamics setup. We study three different configurations, attainable with current technology, where a quantum point contact is coupled galvanically to a coplanar waveguide resonator. Furthermore, we demonstrate that the strong and ultrastrong coupling regimes can be achieved with realistic parameters, allowing the coherent exchange between a superconducting quantum point contact and a quantized intracavity field. 
G. Romero, I. Lizuain, V. S. Shumeiko, E. Solano, and F. S. Bergeret
cond-mat.supr-con cond-mat.mes-hall quant-ph