Measuring and Suppressing Quantum State Leakage in a Superconducting Qubit

被引：171

作者：

Chen, Zijun ^{[1
]}

Kelly, Julian ^{[2
]}

Quintana, Chris ^{[1
]}

Barends, R. ^{[2
]}

Campbell, B. ^{[1
]}

Chen, Yu ^{[2
]}

Chiaro, B. ^{[1
]}

Dunsworth, A. ^{[1
]}

Fowler, A. G. ^{[2
]}

Lucero, E. ^{[2
]}

Jeffrey, E. ^{[2
]}

Megrant, A. ^{[1
,3
]}

Mutus, J. ^{[2
]}

Neeley, M. ^{[2
]}

Neill, C. ^{[1
]}

O'Malley, P. J. J. ^{[1
]}

Roushan, P. ^{[2
]}

Sank, D. ^{[2
]}

Vainsencher, A. ^{[1
]}

Wenner, J. ^{[1
]}

White, T. C. ^{[1
]}

Korotkov, A. N. ^{[4
]}

Martinis, John M. ^{[1
,2
]}

机构：

[1] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA

[2] Google Inc, Santa Barbara, CA 93117 USA

[3] Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA

[4] Univ Calif Riverside, Dept Elect & Comp Engn, Riverside, CA 92521 USA

来源：

PHYSICAL REVIEW LETTERS | 2016年 / 116卷 / 02期

基金：

美国国家科学基金会;

关键词：

Qubits - Quantum optics - Error correction;

D O I：

10.1103/PhysRevLett.116.020501

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Leakage errors occur when a quantum system leaves the two-level qubit subspace. Reducing these errors is critically important for quantum error correction to be viable. To quantify leakage errors, we use randomized benchmarking in conjunction with measurement of the leakage population. We characterize single qubit gates in a superconducting qubit, and by refining our use of derivative reduction by adiabatic gate pulse shaping along with detuning of the pulses, we obtain gate errors consistently below 10(-3) and leakage rates at the 10(-5) level. With the control optimized, we find that a significant portion of the remaining leakage is due to incoherent heating of the qubit.

引用

页数：5

共 35 条

[1] Superconducting quantum circuits at the surface code threshold for fault tolerance [J].

Barends, R. ;

Kelly, J. ;

Megrant, A. ;

Veitia, A. ;

Sank, D. ;

Jeffrey, E. ;

White, T. C. ;

Mutus, J. ;

Fowler, A. G. ;

Campbell, B. ;

Chen, Y. ;

Chen, Z. ;

Chiaro, B. ;

Dunsworth, A. ;

Neill, C. ;

O'Malley, P. ;

Roushan, P. ;

Vainsencher, A. ;

Wenner, J. ;

Korotkov, A. N. ;

Cleland, A. N. ;

Martinis, John M. .

NATURE, 2014, 508 (7497) :500-503

[2] Coherent Josephson Qubit Suitable for Scalable Quantum Integrated Circuits [J].

Barends, R. ;

Kelly, J. ;

Megrant, A. ;

Sank, D. ;

Jeffrey, E. ;

Chen, Y. ;

Yin, Y. ;

Chiaro, B. ;

Mutus, J. ;

Neill, C. ;

O'Malley, P. ;

Roushan, P. ;

Wenner, J. ;

White, T. C. ;

Cleland, A. N. ;

Martinis, John M. .

PHYSICAL REVIEW LETTERS, 2013, 111 (08)

[3] Complete randomized benchmarking protocol accounting for leakage errors [J].

Chasseur, T. ;

Wilhelm, F. K. .

PHYSICAL REVIEW A, 2015, 92 (04)

[4] Optimized driving of superconducting artificial atoms for improved single-qubit gates [J].

Chow, J. M. ;

DiCarlo, L. ;

Gambetta, J. M. ;

Motzoi, F. ;

Frunzio, L. ;

Girvin, S. M. ;

Schoelkopf, R. J. .

PHYSICAL REVIEW A, 2010, 82 (04)

[5] Superconducting quantum bits [J].

Clarke, John ;

Wilhelm, Frank K. .

NATURE, 2008, 453 (7198) :1031-1042

[6]

De A., ARXIV150907905

[7]

DiVincenzo DP, 2000, FORTSCHR PHYS, V48, P771, DOI 10.1002/1521-3978(200009)48:9/11<771::AID-PROP771>3.0.CO

[8]

2-E

[9] Investigating the limits of randomized benchmarking protocols [J].

Epstein, Jeffrey M. ;

Cross, Andrew W. ;

Magesan, Easwar ;

Gambetta, Jay M. .

PHYSICAL REVIEW A, 2014, 89 (06)

[10]

Fang M., 2015, P APS M 2015 AM PHYS, V1, P39002

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