Flux qubits in a planar circuit quantum electrodynamics architecture:   quantum control and decoherence
  We report experiments on superconducting flux qubits in a circuit quantum electrodynamics (cQED) setup. Two qubits, independently biased and controlled, are coupled to a coplanar waveguide resonator. Dispersive qubit state readout reaches a maximum contrast of $72\,\%$. We find intrinsic energy relaxation times at the symmetry point of $7\,\mu\text{s}$ and $20\,\mu\text{s}$ and levels of flux noise of $2.6\,\mu \Phi_0/\sqrt{\text{Hz}}$ and $2.7\,\mu \Phi_0/\sqrt{\text{Hz}}$ at 1 Hz for the two qubits. We discuss the origin of decoherence in the measured devices. These results demonstrate the potential of cQED as a platform for fundamental investigations of decoherence and quantum dynamics of flux qubits. 
J.-L. Orgiazzi, C. Deng, D. Layden, R. Marchildon, F. Kitapli, F.   Shen, M. Bal, F. R. Ong, A. Lupascu
cond-mat.mes-hall cond-mat.supr-con quant-ph