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arXiv · 2405.03896

Quantum sensing in the fractional Fourier domain

Swastik Hegde·David J. Durden·Lakshmy Priya Ajayakumar·Rishi Sivakumar·Mikael P. Backlund
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Abstract

Certain quantum sensing protocols rely on qubits that are initialized, coherently driven in the presence of a stimulus to be measured, then read out. Most widely employed pulse sequences used to drive sensing qubits act locally in either the time or frequency domain. We introduce a generalized set of sequences that effect a measurement in any fractional Fourier domain, i.e. along a linear trajectory of arbitrary angle through the time-frequency plane. Using an ensemble of nitrogen-vacancy centers we experimentally demonstrate advantages in sensing signals with time-varying spectra.

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Swastik Hegde, David J. Durden, Lakshmy Priya Ajayakumar, Rishi Sivakumar, Mikael P. Backlund. 2024-05-06. Quantum sensing in the fractional Fourier domain. https://doi.org/10.1103/physrevapplied.23.024035

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