SFQ control circuits for Josephson junction qubits
SFQ control circuits for Josephson junction qubits
复制标题
用于约瑟夫森结量子位的 SFQ 控制电路
DOI：
10.1109/tasc.2003.814114
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发表时间：
2003
影响因子：
1.8
通讯作者：
D. Averin
中科院分区：
文献类型：
--
作者：
V. Semenov;D. Averin
三种类型的设备：需要磁脉冲发生器、读出电路和控制它们的数字电路来支持基于约瑟夫森结量子位的量子逻辑的可缩放操作。RSFQ技术提供了实现这种量子电路经典接口的最自然的框架。在这项工作中，我们认为，然而，特定的量子位的要求不能满足传统的RSFQ方法，并描述了必要的修改。本文提出了一种基于两个长欠阻尼约瑟夫森结的脉冲发生器的新结构，其特点是降低了功耗和输出噪声。我们还展示了如何权衡功耗和速度的数字控制电路使用约瑟夫森结的分流电阻值相似，但非常不同的临界电流。最后，我们提出了一种新的读出电路，使动态补偿的反作用下降到接近基本量子力学极限的水平。
Devices of three types: magnetic pulse generators, read-out circuits, and digital circuits controlling them are needed to support scalable operation of quantum logic based on the Josephson junction qubits. The most natural framework for implementation of such a classical interface to quantum circuits is provided by the RSFQ technology . In this work, we argue, however, that specific qubit requirements can not be satisfied with the conventional RSFQ approach and describe the necessary modifications. We suggest a new structure of the pulse generator based on two long underdamped Josephson junctions which is characterized by the reduced power consumption and reduced output noise. We also show how to trade off power consumption and speed of the digital control circuits by using Josephson junctions with similar values of the shunt resistors but very different critical currents. Finally, we suggest a new read-out circuit which enables dynamic compensation of the backaction down to the level approaching fundamental quantum-mechanical limit.