Bucher, DominikGlenn, David R.Park, HongkunLukin, Mikhail D.Walsworth, Ronald L.2023-08-152020-06-09Bucher, Dominik, David R. Glenn, Hongkun Park, Mikhail D. Lukin, Ronald L. Walsworth. "Hyperpolarization-Enhanced NMR Spectroscopy with Femtomole Sensitivity Using Quantum Defects in Diamond." Phys. Rev. X 10, no. 2 (2020). DOI: 10.1103/physrevx.10.0210532160-3308https://nrs.harvard.edu/URN-3:HUL.INSTREPOS:37376791Nuclear 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 the state-of-the-art of mass-limited NMR spectroscopy, opening the door to new applications at the picoliter-scale in drug and natural product discovery, catalysis research, and single cell studies.en-USGeneral Physics and AstronomyJournal Article2023-08-1510.1103/physrevx.10.021053