Fitting time-dependent Markovian dynamics to noisy quantum channels

• URL: http://arxiv.org/abs/2303.08936v1
• Date: Wed, 15 Mar 2023 21:05:13 GMT
• Title: Fitting time-dependent Markovian dynamics to noisy quantum channels
• Authors: Emilio Onorati, Tamara Kohler, Toby S. Cubitt
• Abstract summary: Understanding how to characterise and mitigate errors is a key challenge in developing reliable quantum architecture for near-term applications. Recent work provides an efficient set of algorithms for analysing unknown noise processes. We present an extension of the scheme now able to analyse noisy dynamics with time-dependent generators from a sequence of snapshots.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Understanding how to characterise and mitigate errors is a key challenge in developing reliable quantum architecture for near-term applications. Recent work (arXiv:2103.17243) provides an efficient set of algorithms for analysing unknown noise processes requiring only tomographic snapshots of the quantum operator under consideration, without the need of any a-priori information on the noise model, nor necessitating a particular experimental setup. The only assumption made is that the observed channel can be approximated by a time-independent Markovian map, which is a typically reasonable framework when considering short time scales. In this note we lift the time-independent assumption, presenting an extension of the scheme now able to analyse noisy dynamics with time-dependent generators from a sequence of snapshots. We hence provide a diagnostic tool for a wider spectrum of instances while inheriting all the favourable features from the previous protocol. On the theoretical side, the problem of characterising time-dependent Markovian channels has been an open problem for many decades. This work gives an approach to tackle this characterisation problem rigorously.

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