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arXiv · 1707.01902

Limits on Spectral Resolution Measurements by Quantum Probes

Amit Rotem·Tuvia Gefen·Santiago Oviedo-Casado·Javier Prior·Simon Schmitt·Yoram Burak·Liam McGuiness·Fedor Jelezko·Alex Retzker
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Abstract

The limits of frequency resolution in nano-NMR experiments have been discussed extensively in recent years. It is believed that there is a crucial difference between the ability to resolve a few frequencies and the precision of estimating a single one. Whereas the efficiency of single frequency estimation gradually increases with the square root of the number of measurements, the ability to resolve two frequencies is limited by the specific timescale of the signal and cannot be compensated for by extra measurements. Here we show theoretically and demonstrate experimentally that the relationship between these quantities is more subtle and both are only limited by the Cram\'er-Rao bound of a single frequency estimation.

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Amit Rotem, Tuvia Gefen, Santiago Oviedo-Casado, Javier Prior, Simon Schmitt, Yoram Burak, Liam McGuiness, Fedor Jelezko, Alex Retzker. 2017-07-06. Limits on Spectral Resolution Measurements by Quantum Probes. https://doi.org/10.1103/physrevlett.122.060503

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