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arXiv · 1702.07408

Control methods for improved Fisher information with quantum sensing

Tuvia Gefen·Fedor Jelezko·Alex Retzker
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Abstract

Recently new approaches for sensing the frequency of time dependent Hamiltonians have been presented, and it was shown that the optimal Fisher information scales as $T^{4}.$ We present here our interpretation of this new scaling, where the relative phase is accumulated quadratically with time, and show that this can be produced by a variety of simple pulse sequences. Interestingly, this scaling has a limited duration, and we show that certain pulse sequences prolong the effect. The performance of these schemes is analyzed and we examine their relevance to state-of-the-art experiments. We analyze the $T^{3}$ scaling of the Fisher information which appears when multiple synchronized measurements are performed, and is the optimal scaling in the case of a finite coherence time.

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Tuvia Gefen, Fedor Jelezko, Alex Retzker. 2017-06-28. Control methods for improved Fisher information with quantum sensing. https://doi.org/10.1103/physreva.96.032310

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