Understanding crosstalk in quantum processors

Abstract: Model-based quantum tomography protocols like gate set tomography optimize a noise model with some number of parameters in order to fit experimental data. As the number of qubits increases, two issues emerge: 1) the number of model parameters grows, and 2) the cost of propagating quantum states (density matrices) increases exponentially. The first issue can be addressed by considering reduced models that limit errors to being low-weight and geometrically local.

In this talk, we focus on the second issue and present a method for performing approximate density matrix propagation based on perturbative expansions of error generators. The method is tailored to the likelihood optimization problem faced by model-based tomography protocols. We will discuss the advantages and drawbacks of using this method when characterizing the errors in up to 8-qubit systems.

quantum computing and information

Audience: researchers in the topic

( paper )

Comments: Hosted by A/Prof Chris Ferrie, UTS Centre for Quantum Software and Information.

Please note, Erik Nielsen's seminar will follow directly after Robin Blume-Kohout's seminar.

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Centre for Quantum Software and Information Seminar Series

Series comments: To request the zoom link, please send a message to: cqsiadmin@uts.edu.au using your business/organisation/institution email address. Watch previous seminars on YouTube: - QSI Seminar Series 2021 (https://youtube.com/playlist?list=PLux7B14QYkPbDDOpqKSWScHXHodiBwr48) - QSI Seminar Series 2020 (https://youtube.com/playlist?list=PLux7B14QYkPZREUXReOq01ewLl02QXBXa)

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