A random-walk benchmark for single-electron circuits

authored by
David Reifert, Martins Kokainis, Andris Ambainis, Vyacheslavs Kashcheyevs, Niels Ubbelohde

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.

External Organisation(s)
National Metrology Institute of Germany (PTB)
University of Latvia
Nature Communications
Publication date
Publication status
Peer reviewed
ASJC Scopus subject areas
Chemistry(all), Biochemistry, Genetics and Molecular Biology(all), Physics and Astronomy(all)
Electronic version(s)
https://doi.org/10.1038/s41467-020-20554-w (Access: Open)