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arXiv · 2008.09716

Quantum Fourier transform for quantum sensing

Vadim Vorobyov·Sebastian Zaiser·Nikolas Abt·Jonas Meinel·Durga Dasari·Philipp Neumann·Jörg Wrachtrup
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Abstract

The Quantum Fourier Transformation ($QFT$) is a key building block for a whole wealth of quantum algorithms. Despite its proven efficiency, only a few proof-of-principle demonstrations have been reported. Here we utilize $QFT$ to enhance the performance of a quantum sensor. We implement the $QFT$ algorithm in a hybrid quantum register consisting of a nitrogen-vacancy (NV) center electron spin and three nuclear spins. The $QFT$ runs on the nuclear spins and serves to process the sensor - NV electron spin signal. We demonstrate $QFT$ for quantum (spins) and classical signals (radio frequency (RF) ) with near Heisenberg limited precision scaling. We further show the application of $QFT$ for demultiplexing the nuclear magnetic resonance (NMR) signal of two distinct target nuclear spins. Our results mark the application of a complex quantum algorithm in sensing which is of particular interest for high dynamic range quantum sensing and nanoscale NMR spectroscopy experiments.

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Vadim Vorobyov, Sebastian Zaiser, Nikolas Abt, Jonas Meinel, Durga Dasari, Philipp Neumann, Jörg Wrachtrup. 2020-08-21. Quantum Fourier transform for quantum sensing. https://doi.org/10.1038/s41534-021-00463-6

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