论文标题
可调超导速度量子与长相干时间
Tunable superconducting flux qubits with long coherence times
论文作者
论文摘要
在这项工作中，我们研究了一系列可调通量速度，该速度是在蓝宝石底物上制造的Coplanar波导谐振器的电感耦合。每个量子位包括一个不对称的超导量子干扰装置，该设备由外部磁场的应用控制并充当可调的约瑟夫森连接。 Qubits的可调性通常为$ \ pm 3.5 $ GHz，其中央间隙频率周围。测得的放松时间受基板的介电损失的限制，并且可以达到$ t_ {1} \ sim8μs$。即使在最佳点处，回声驱动时间也受到通量噪声的限制，并达到$ t_ {2e} \ sim4μs$，几乎比可调通量量子的最先进的订单长。
In this work, we study a series of tunable flux qubits inductively coupled to a coplanar waveguide resonator fabricated on a sapphire substrate. Each qubit includes an asymmetric superconducting quantum interference device which is controlled by the application of an external magnetic field and acts as a tunable Josephson junction. The tunability of the qubits is typically $\pm 3.5$ GHz around their central gap frequency. The measured relaxation times are limited by dielectric losses in the substrate and can attain $T_{1}\sim 8 μs$. The echo dephasing times are limited by flux noise even at optimal points and reach $T_{2E}\sim 4 μs$, almost an order of magnitude longer than state of the art for tunable flux qubits.
