ARC Centre of Excellence for Engineered Quantum Systems, School of Mathematics and Physics, The University of Queensland, Brisbane, Queensland 4072, Australia.
Institute for Theoretical Physics, ETH Zürich, 8093 Zürich, Switzerland.
Phys Rev Lett. 2018 May 25;120(21):213602. doi: 10.1103/PhysRevLett.120.213602.
We present the design of a passive, on-chip microwave circulator based on a ring of superconducting tunnel junctions. We investigate two distinct physical realizations, based on Josephson junctions (JJs) or quantum phase slip elements (QPS), with microwave ports coupled either capacitively (JJ) or inductively (QPS) to the ring structure. A constant bias applied to the center of the ring provides an effective symmetry breaking field, and no microwave or rf bias is required. We show that this design offers high isolation, robustness against fabrication imperfections and bias fluctuations, and a bandwidth in excess of 500 MHz for realistic device parameters.
我们提出了一种基于超导隧道结环的无源片上微波环行器的设计。我们研究了两种基于约瑟夫森结（JJ）或量子相位滑移元件（QPS）的不同物理实现，微波端口通过电容（JJ）或电感（QPS）耦合到环结构。施加在环中心的恒定偏置提供了有效的对称破场，不需要微波或射频偏置。我们表明，这种设计具有高隔离度、对制造缺陷和偏置波动的鲁棒性，以及超过 500MHz 的带宽，对于实际器件参数来说是非常可观的。
