Flux Qubits and Readout Device with Two Independent Flux Lines
  We report measurements on two superconducting flux qubits coupled to a readout Superconducting QUantum Interference Device (SQUID). Two on-chip flux bias lines allow independent flux control of any two of the three elements, as illustrated by a two-dimensional qubit flux map. The application of microwaves yields a frequency-flux dispersion curve for 1- and 2-photon driving of the single-qubit excited state, and coherent manipulation of the single-qubit state results in Rabi oscillations and Ramsey fringes. This architecture should be scalable to many qubits and SQUIDs on a single chip. 
B.L.T. Plourde, T.L. Robertson, P.A. Reichardt, T. Hime, S. Linzen,   C.-E. Wu, and John Clarke