TY - JOUR

T1 - A random-walk benchmark for single-electron circuits

AU - Reifert, David

AU - Kokainis, Martins

AU - Ambainis, Andris

AU - Kashcheyevs, Vyacheslavs

AU - Ubbelohde, Niels

N1 - Funding information: We acknowledge T. Gerster, L. Freise, H. Marx, K. Pierz, and T. Weimann for support in device fabrication, J. Valeinis for discussions. D.R. additionally acknowledges funding by the Deutsche Forschungsgemeinschaft (DFG) under Germany’s Excellence Strategy— EXC-2123 —90837967, as well as the support of the Braunschweig International Graduate School of Metrology B-IGSM. M.K., A.A., and V.K are supported by Latvian Council of Science (grant no. lzp-2018/1-0173). A.A. also acknowledges support by ‘Quantum algorithms: from complexity theory to experiment’ funded under ERDF program 1.1.1.5. Open Access funding enabled and organized by Projekt DEAL.

PY - 2021/1/12

Y1 - 2021/1/12

N2 - Mesoscopic integrated circuits aim for precise control over elementary quantum systems. However, as fidelities improve, the increasingly rare errors and component crosstalk pose a challenge for validating error models and quantifying accuracy of circuit performance. Here we propose and implement a circuit-level benchmark that models fidelity as a random walk of an error syndrome, detected by an accumulating probe. Additionally, contributions of correlated noise, induced environmentally or by memory, are revealed as limits of achievable fidelity by statistical consistency analysis of the full distribution of error counts. Applying this methodology to a high-fidelity implementation of on-demand transfer of electrons in quantum dots we are able to utilize the high precision of charge counting to robustly estimate the error rate of the full circuit and its variability due to noise in the environment. As the clock frequency of the circuit is increased, the random walk reveals a memory effect. This benchmark contributes towards a rigorous metrology of quantum circuits.

AB - Mesoscopic integrated circuits aim for precise control over elementary quantum systems. However, as fidelities improve, the increasingly rare errors and component crosstalk pose a challenge for validating error models and quantifying accuracy of circuit performance. Here we propose and implement a circuit-level benchmark that models fidelity as a random walk of an error syndrome, detected by an accumulating probe. Additionally, contributions of correlated noise, induced environmentally or by memory, are revealed as limits of achievable fidelity by statistical consistency analysis of the full distribution of error counts. Applying this methodology to a high-fidelity implementation of on-demand transfer of electrons in quantum dots we are able to utilize the high precision of charge counting to robustly estimate the error rate of the full circuit and its variability due to noise in the environment. As the clock frequency of the circuit is increased, the random walk reveals a memory effect. This benchmark contributes towards a rigorous metrology of quantum circuits.

UR - http://www.scopus.com/inward/record.url?scp=85099228707&partnerID=8YFLogxK

U2 - 10.1038/s41467-020-20554-w

DO - 10.1038/s41467-020-20554-w

M3 - Article

C2 - 33436588

AN - SCOPUS:85099228707

VL - 12

JO - Nature Communications

JF - Nature Communications

SN - 2041-1723

IS - 1

M1 - 285

ER -