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arXiv · 1809.02972

The dynamical-decoupling-based spatiotemporal noise spectroscopy

Jan Krzywda·Piotr Szańkowski·Łukasz Cywiński
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Abstract

Here we demonstrate how the standard, temporal-only, dynamical-decoupling-based noise spectroscopy method can be extended to also encompass the spatial degree of freedom. This spatiotemporal spectroscopy utilizes a system of multiple qubits arranged in a line that are undergoing pure dephasing due to environmental noise. When the qubits are driven by appropriately coordinated sequences of $π$ pulses the multi-qubit register becomes decoupled from all components of the noise, except for those characterized by frequencies and wavelengths specified by the pulse sequences. This allows for employment of the procedure for reconstruction of the two-dimensional spectral density that quantifies the power distribution among spatial and temporal harmonic components of the noise.

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Jan Krzywda, Piotr Szańkowski, Łukasz Cywiński. 2019-04-18. The dynamical-decoupling-based spatiotemporal noise spectroscopy. https://doi.org/10.1088/1367-2630%2Fab0ce7

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