Multiqubit noise deconvolution and characterization

Autor: Roncallo, Simone, Maccone, Lorenzo, Macchiavello, Chiara
Rok vydání: 2022
Předmět:
Zdroj: Phys. Rev. A 107, 022419 (2023)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevA.107.022419
Popis: We present a noise deconvolution technique for obtaining noiseless expectation values of noisy observables at the output of multiqubit quantum channels. For any number of qubits or in the presence of correlations, our protocol applies to any mathematically invertible noise model, even when its inverse map is not physically implementable, i.e. when it is neither completely-positive nor trace-preserving. For a generic observable affected by Pauli noise it provides a quadratic speedup, always producing a rescaling of its Pauli basis components. We show that it is still possible to achieve the deconvolution while experimentally estimating the noise parameters, whenever these are unknown (bypassing resource-heavy techniques such as quantum process tomography). We provide a simulation, with examples for both Pauli and non-Pauli channels.
Comment: 8 pages, 2 figures; [v2] Introductory figure added; Overall improvements and simplifications; [v3] Minor improvements and corrections
Databáze: arXiv