We report experiments on superconducting flux qubits in a circuit quantumelectrodynamics (cQED) setup. Two qubits, independently biased and controlled,are coupled to a coplanar waveguide resonator. Dispersive qubit state readoutreaches a maximum contrast of $72\,\%$. We find intrinsic energy relaxationtimes at the symmetry point of $7\,\mu\text{s}$ and $20\,\mu\text{s}$ andlevels 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 ofdecoherence in the measured devices. These results demonstrate the potential ofcQED as a platform for fundamental investigations of decoherence and quantumdynamics of flux qubits.
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机译：我们报告了在电路量子电动力学（cQED）装置中超导通量量子位的实验。独立偏置和控制的两个量子位耦合到共面波导谐振器。分散的量子位状态读数达到$ 72 \，\％$的最大对比度。我们发现在$ 7 \，\ mu \ text {s} $和$ 20 \，\ mu \ text {s} $的对称点处的固有能量弛豫时间以及$ 2.6 \，\ mu \ Phi_0 / \ sqrt {\两个量子位在1 Hz处的文本{Hz}} $和$ 2.7 \，\ mu \ Phi_0 / \ sqrt {\ text {Hz}} $。我们讨论了被测设备中退相干的起源。这些结果证明了cQED作为平台研究通量量子位的退相干和量子动力学的潜力。
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