Improving wafer-scale Josephson junction resistance variation in superconducting quantum coherent circuits
Improving wafer-scale Josephson junction resistance variation in superconducting quantum coherent circuits
复制标题
DOI：
10.1088/1361-6668/ab8617
复制
发表时间：
2020-06-01
影响因子：
3.6
通讯作者：
Siddiqi, I
中科院分区：
文献类型：
--
作者：
Kreikebaum, J. M.;O'Brien, K. P.;Siddiqi, I
量子比特是为下一代计算机和探测器设想的相干电路的一个例子。相干寿命为0 （100 μ s）的鲁棒超导量子位是transmon：一个约瑟夫森结作为非线性电感器与电容器分流形成非谐波振荡器。在具有许多这样的传输器的复杂设备中，通常需要精确控制每个量子位频率，因此必须充分减少结面积和隧道势垒厚度的变化，以达到最佳性能，同时避免相邻电路之间的频谱重叠。简单地将我们针对单个独立器件优化的配方移植到晶圆规模（从150mm晶圆生产64,1x1 cm的晶圆），最初导致室温隧穿电阻的全球漂移为+/- 30%。推断临界电流Ic
Quantum bits, or qubits, are an example of coherent circuits envisioned for next-generation computers and detectors. A robust superconducting qubit with a coherent lifetime of O(100 mu s) is the transmon: a Josephson junction functioning as a non-linear inductor shunted with a capacitor to form an anharmonic oscillator. In a complex device with many such transmons, precise control over each qubit frequency is often required, and thus variations of the junction area and tunnel barrier thickness must be sufficiently minimized to achieve optimal performance while avoiding spectral overlap between neighboring circuits. Simply transplanting our recipe optimized for single, stand-alone devices to wafer-scale (producing 64, 1x1 cm dies from a 150 mm wafer) initially resulted in global drifts in room-temperature tunneling resistance of +/- 30%. Inferring a critical current Ic