Optimizing Measurement Strengths for Qubit Quasiprobabilities Behind Out-of-Time-Ordered Correlators
Document Type
Article
Publication Date
12-27-2019
Abstract
Out-of-time-ordered correlators (OTOCs) have been proposed as a tool to witness quantum information scrambling in many-body system dynamics. These correlators can be understood as averages over nonclassical multitime quasiprobability distributions (QPDs). These QPDs have more information and their nonclassical features witness quantum information scrambling in a more nuanced way. However, their high dimensionality and nonclassicality make QPDs challenging to measure experimentally. We focus on the topical case of a many-qubit system and show how to obtain such a QPD in the laboratory using circuits with three and four sequential measurements. Averaging distinct values over the same measured distribution reveals either the OTOC or parameters of its QPD. Stronger measurements minimize experimental resources despite increased dynamical disturbance.
Recommended Citation
R. Mohseninia, J. R. G. Alonso, and J. Dressel, Optimizing Measurement Strengths for Qubit Quasiprobabilities Behind Out-of-Time-Ordered Correlators, Phys. Rev. A. 100, 062336 (2019).
Peer Reviewed
1
Copyright
American Physical Society
Comments
This article was originally published in Journal, volume number, issue number, in year. https://doi.org/10.1103/PhysRevA.100.062336