Filtering crosstalk from bath non-Markovianity via spacetime classical shadows

Abstract

From an open system perspective non-Markovian effects due to a nearby bath or neighbouring qubits are dynamically equivalent. However, there is a conceptual distinction to account for: neighbouring qubits may be controlled. We combine recent advances in non-Markovian quantum process tomography with the framework of classical shadows to characterise spatiotemporal quantum correlations. Observables here constitute operations applied to the system, where the free operation is the maximally depolarising channel. Using this as a causal break, we systematically erase causal pathways to narrow down the progenitors of temporal correlations. We show that one application of this is to filter out the effects of crosstalk and probe only non-Markovianity from an inaccessible bath. It also provides a lens on spatiotemporally spreading correlated noise throughout a lattice from common environments. We demonstrate both examples on synthetic data. Owing to the scaling of classical shadows, we can erase arbitrarily many neighbouring qubits at no extra cost. Our procedure is thus efficient and amenable to systems even with all-to-all interactions.

5 pages, 4 figures

References in corpus (13)

• Quantum advantage in learning from experiments
• The randomized measurement toolbox
• Operational Markov condition for quantum processes
• Information-theoretic bounds on quantum advantage in machine learning
• Provably efficient machine learning for quantum many-body problems
• Gate Set Tomography
• Quantum stochastic processes and quantum non-Markovian phenomena
• Non-Markovian Quantum Process Tomography
• Quantum crosstalk cancellation for fast entangling gates and improved multi-qubit performance
• Experimental Characterization of Crosstalk Errors with Simultaneous Gate Set Tomography
• Randomized benchmarking for non-Markovian noise
• Frame-Based Filter-Function Formalism for Quantum Characterization and Control
• Impact of correlations and heavy-tails on quantum error correction

Cited by in corpus (12)

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• Operational Markovianization in Randomized Benchmarking
• Quantum processes as thermodynamic resources: the role of non-Markovianity
• Randomised benchmarking for characterizing and forecasting correlated processes
• Relations between Markovian and non-Markovian correlations in multitime quantum processes
• Noise-adapted Quantum Error Correction for Non-Markovian Noise
• Unifying non-Markovian characterisation with an efficient and self-consistent framework
• Process tensor distinguishability measures
• Markovian to non-Markovian phase transition in the operator dynamics of a mobile impurity
• Robust Error Accumulation Suppression for Quantum Circuits
• Classical Shadows with Improved Median-of-Means Estimation