Forn-Díaz, P. (author), Lisenfeld, J. (author), Marcos, D. (author), García-Ripoll, J.J. (author), Solano, E. (author), Harmans, C.J.P.M. (author), Mooij, J.E. (author) We measure the dispersive energy-level shift of an LC resonator magnetically coupled to a superconducting qubit, which clearly shows that our system operates in the ultrastrong coupling regime. The large mutual kinetic inductance provides a coupling energy of ?0.82??GHz, requiring the addition of counter-rotating-wave terms in the description of...
journal article 2010
