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arXiv · 2105.08381

Phase sensitive quantum spectroscopy with high frequency resolution

Nicolas Staudenmaier·Simon Schmitt·Liam P. McGuinness·Fedor Jelezko
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Abstract

Classical sensors for spectrum analysis are widely used but lack micro- or nanoscale spatial resolution. On the other hand, quantum sensors, capable of working with nanoscale precision, do not provide precise frequency resolution over a wide range of frequencies. Using a single spin in diamond, we present a measurement protocol for quantum probes which enables full signal reconstruction on a nanoscale spatial resolution up to potentially 100\,GHz. We achieve $58\,\mathrm{nT/\sqrt{Hz}}$ amplitude and $0.095\,\mathrm{rad/\sqrt{Hz}}$ phase sensitivity and a relative frequency uncertainty of $10^{-12}$ for a $1.51\,\mathrm{GHz}$ signal within $10\,\mathrm{s}$ of integration. This technique opens the way to quantum spectrum analysis methods with potential applications in electron spin detection and nanocircuitry in quantum technologies.

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Nicolas Staudenmaier, Simon Schmitt, Liam P. McGuinness, Fedor Jelezko. 2021-05-18. Phase sensitive quantum spectroscopy with high frequency resolution. https://doi.org/10.1103/physreva.104.l020602

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