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arXiv · 2006.03910

Micron-scale SABRE-enhanced NV-NMR Spectroscopy

Nithya Arunkumar·Dominik B. Bucher·Matthew J. Turner·Patrick TomHon·David Glenn·Soren Lehmkuhl·Mikhail D. Lukin·Hongkun Park·Matthew S. Rosen·Thomas Theis·Ronald L. Walsworth
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Abstract

Optically-probed nitrogen-vacancy (NV) quantum defects in diamond can detect nuclear magnetic resonance (NMR) signals with high-spectral resolution from micron-scale sample volumes of about 10 picoliters. However, a key challenge for NV-NMR is detecting samples at millimolar concentrations. Here, we demonstrate an improvement in NV-NMR proton concentration sensitivity of about $10^5$ over thermal polarization by hyperpolarizing sample proton spins through signal amplification by reversible exchange (SABRE), enabling micron-scale NMR of small molecule sample concentrations as low as 1 millimolar in picoliter volumes. The SABRE-enhanced NV-NMR technique may enable detection and chemical analysis of low concentration molecules and their dynamics in complex micron-scale systems such as single-cells.

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Nithya Arunkumar, Dominik B. Bucher, Matthew J. Turner, Patrick TomHon, David Glenn, Soren Lehmkuhl, Mikhail D. Lukin, Hongkun Park, Matthew S. Rosen, Thomas Theis, Ronald L. Walsworth. 2020-06-06. Micron-scale SABRE-enhanced NV-NMR Spectroscopy. https://doi.org/10.1103/prxquantum.2.010305

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