Symmetrization methods for characterization and benchmarking of quantum processes

Abstract

The detailed characterization of controlled quantum processes is a fundamental problem in experimental physics, and is a crucial requirement for the development of robust quantum information processing. Standard approaches for complete characterization of a quantum process require an number of experiments that grows exponentially with the number of interacting subsystems. Hence these methods are infeasible for many situations of practical interest. This paper reviews recent approaches to process estimation that overcome this problem by identifying subsets of the information that is of practical interest, and then demonstrating how this partial information can be estimated through the application of symmetrizing operations.Résumé : La caractérisation détaillée des mécanismes quantiques contrôlés est un problème fondamental en physique expérimentale et une besoin crucial dans le développement de méthodes fiables de traitement de l'information quantique. Les approches standard pour caractériser de façon complète un mécanisme quantique requièrent des expériences en nombre croissant exponentiellement avec le nombre de sous-systèmes qui y jouent un rôle. Il en ressort que ces approches sont essentiellement inutiles pour les cas d'intérêt pratique. Nous passons ici en revue les approches qui surmontent ce problème, en estimant directement de l'information partielle d'intérêt pratique par le biais d'opérations de symétrisation.[Traduit par la Rédaction]

Few‐Qubit Magnetic Resonance Quantum Information Processors: Simulating Chemistry and Physics

“…If the noise exceeds this threshold, control must be improved until the threshold is attained. It is possible to assess the noise level using benchmarking [32,33]. In an NMR system where control was optimized, it has been possible to reach an error per gate rate of 10 −4 for single-qubit gates and 10 −3 for two-qubit gates [34].…”

Recent advances in nuclear magnetic resonance quantum information processing

“…If the noise exceeds this threshold, control must be improved until the threshold is attained. It is possible to assess the noise level using benchmarking [16,17]. In a system where control was optimized, it has been possible to reach an error-per-gate rate of 10 −4 for single-qubit gates and 10 −3 for two-qubit gates [18].…”