Minimising statistical errors in calibration of quantum-gate sets

arXiv (Cornell University)

Abstract

Calibration of quantum gates is a necessary hurdle to overcome on the way to a reliable quantum computer. In a recent paper, a protocol called Gate Set Calibration protocol (GSC) has been introduced and used to learn coherent errors from multi-qubit quantum gates. Here, we extend this study in a number of ways: First, we perform a statistical analysis of the measurement uncertainties. Second, we find explicit measurement settings that minimize this uncertainty, while also requiring that the protocol involves only a small number of distinct gates, aiding physical realizability. We numerically demonstrate that, just by adding two more single-qubit gates to GSC, the statistical error produced in the calibration of a CNOT gate is divided by a factor of more than two.

Authors 3

1. Yaiza Aragonés-Soria

   University of Cologne

   Affiliation as printed

   Institute for Theoretical Physics , University of Cologne , Zülpicher Str. 77 , 50937 Köln , Germany

2. Tobias Hangleiter Aachen

   RWTH Aachen University · Forschungszentrum Jülich · Jülich Aachen Research Alliance

   Affiliation as printed

   JARA-FIT Institute for Quantum Information , Forschungszentrum Jülich GmbH and

   RWTH Aachen University , 52074 Aachen , Germany

3. Pascal Cerfontaine

   Forschungszentrum Jülich · Jülich Aachen Research Alliance

   Affiliation as printed

   JARA-FIT Institute for Quantum Information , Forschungszentrum Jülich GmbH and