Nuclear magnetic resonance (NMR) spectroscopy is a widely used tool for chemical analysis and molecular structure identification. Because it typically relies on the weak magnetic fields produced by a small thermal nuclear spin polarization, NMR suffers from poor molecule-number sensitivity compared to other analytical techniques. Recently, a new class of NMR sensors based on optically-probed nitrogen-vacancy (NV) quantum defects in diamond have allowed molecular spectroscopy from sample volumes several orders of magnitude smaller than the most sensitive inductive detectors. To date, however, NV-NMR spectrometers have only been able to observe signals from pure, highly concentrated samples. To overcome this limitation, we introduce a technique that combines picoliter-scale NV-NMR with fully integrated Overhauser dynamic nuclear polarization (DNP) to perform high-resolution spectroscopy on a variety of small molecules in dilute solution, with femtomole sensitivity. Our technique advances mass-limited NMR spectroscopy for drug and natural product discovery, catalysis research, and single cell studies.
@article{arxiv.1810.02408,
title = {Hyperpolarization-enhanced NMR spectroscopy with femtomole sensitivity using quantum defects in diamond},
author = {Dominik B. Bucher and David R. Glenn and Hongkun Park and Mikhail D. Lukin and Ronald L. Walsworth},
journal= {arXiv preprint arXiv:1810.02408},
year = {2020}
}