宿非凡,杨钊华

• 1:中国科学院物理研究所北京凝聚态物理国家研究中心

摘要(Abstract)：

把多个超导量子比特耦合起来并实现对它们的测控是实现超导量子计算的重要一步。作为“物理前沿介绍——超导量子计算”系列的第四篇，本文系统阐述超导量子比特耦合，操控与测量的物理原理，并给出了一套基本的量子操控与测量的流程。作为例子对新近一些超导量子比特实验的设计方案进行讨论，最后对超导量子比特测控基础表征过程给出统一的流程图，并对超导量子计算进行了展望。本文旨在帮助广大高校物理专业教师、高年级本科生、研究生以及对超导量子计算感兴趣的理工科背景读者系统了解操控与测量超导量子比特的物理原理。

关键词(KeyWords)： 超导量子比特;微波测控技术;量子比特表征

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 宿非凡,杨钊华

参考文献(References)：

• [1] WANG C L et al.Transmon qubit with relaxation time exceeding 0.5 milliseconds.arXiv:2105.09890.
• [2] BRAGINSKY B,KHALILI F.Quantum nondemolition measurements:The route from toys to tools[J].Reviews of Modern Physics,1996(68):1-11.
• [3] SU F F,YANG Z H,ZHAO S K,et al.Fabrication and characterization of superconducting multiqubit device with niobium base layer[J].Chin.Phys.B,2021,30 100304.
• [4] BLAIS A,HUANG R,WALLRAFF A,et al.Cavity quantum electrodynamics for superconducting electrical circuits:An architecture for quantum computation[J].Phys.Rev.A,2004,69:062320.
• [5] KRANTZ P,KJAERGAARD M,YAN F,et al.A Quantum engineer's guide to superconducting qubits[J].arXiv:1904.06560v2 30 Apr 2019.
• [6] KOCH J,YU T,GAMBETTA J,et al.Charge-insensitive qubit design derived from the cooper pair box[J].Phys.Rev.A,2007,76:042391.
• [7] PETERER M,BADER S,JIN X,et al.Coherence and decay of higher energy levels of a superconducting transmon qubit[J].Phys.Rev.Lett.,2015,114:010501.
• [8] TINKHAM M.Introduction to superconductivity[M].New York:Dover publications,2004.
• [9] MCKAY D,FILIPP S,MEZZACAPO A,et al.Universal gate for fixed-frequency qubits via a tunable bus[J].Phys.Rev.Applied,2016,6:064007.
• [10] David M.Pozar.微波工程技术[M].3版.北京：电子工业出版社.
• [11] SURI B.Transmon qubits coupled to superconducting lumped element resonators[Z].2015.
• [12] KHALIL M S,STOUTIMORE M J,WELLSTOOD F C,et al.An analysis method for asymmetric resonator transmission applied to superconducting devices[J].J.Appl.Phys.111,054510,2012.
• [13] SANK D.Fast,accurate state measurement in superconducting qubits[Z].2014.
• [14] SANGIL K,AKIYOSHI T,GOPIKA L B,et al.Gate-based superconducting quantum computing[J].J.Appl.Phys.,129,041102,2021.
• [15] 宿非凡.超导电路的量子化方法[J].物理与工程，2021,31(3):13-15,21.SU F F.The quantization method of superconducting circuit[J].Physics and Engineering,2021,31(3):13-15,21.(in Chinese)
• [16] 宿非凡，杨钊华.约瑟夫森效应与超导量子电路的基本物理原理[J].物理与工程，2021,31(5):28-33.SU F F,YANG Z H.Josephson effect and the basic physical principles of superconducting quantum circuits[J].Physics and Engineering,2021,31(5):28-33.(in Chinese)
• [17] 宿非凡，杨钊华.超导量子比特能谱[J].物理与工程，2021,31(6):73-83,96SU F F,YANG.Z.H.Superconducting qubit spectrum[J].Physics and Engineering,2021,31(6):73-83,96.(in Chinese)
• [18] BARENDS R,et al.Coherent Josephson qubit suitable for scalable quantum integrated circuits[J].Phys.Rev.L,111,080502,2013.
• [19] BLOCH F.Nuclear induction[J].Physical Review,1946,70:7-8.
• [20] BLOCHF.Generalized theory of relaxation[J].Phys.Rev.,1957,105:1206-1222.
• [21] REDFIELD G.On the theory of relaxation processes[J].IBM Journal of Resarch and Development.1957,1:1206-122.
• [22] KOCH R,DIVINCENZO D,CLARKE J.Model for 1/f flflux noise in squids and qubits[J].Phys.Rev.Lett.,2007,98:267003.
• [23] CATELANI G,NIGG S,GIRVIN S,et al.Decoherence of superconducting qubits caused by quasiparticle tunneling[J].Phys.Rev.B,2012,86:184514.
• [24] RAMSEY N.A molecular beam resonance method with separated oscillating fifields[J].Phys.Rev.,1950,78:695-699.
• [25] AVERIN D V,et al.Suppression of dephasing by qubit motion in superconducting circuits[J].Phys.Rev.Lett.,2016,116,010501.
• [26] HAHN E.Spin echoes[J].Phys.Rev.,1950,80:580-594.
• [27] BYLANDER J,GUSTAVSSON S,YAN F,et al.Noise spectroscopy through dynamical decoupling with a superconducting flux qubit[J].Nature Physics,2011,7:565-570.