Enhanced microscale NMR spectroscopy of low-gyromagnetic ratio nuclei via hydrogen transfer

TL;DR

This paper introduces a novel NMR spectroscopy method using NV centers and hydrogen transfer to enhance detection sensitivity of low-gyromagnetic-ratio nuclei at the microscale, enabling better structural analysis.

Contribution

The work presents a new technique that significantly improves sensitivity for detecting low-gyromagnetic-ratio nuclei in NMR spectroscopy using NV centers and hydrogen transfer.

Findings

Sensitivity improved by over an order of magnitude for 13C

Effective under high magnetic fields

Applicable to nuclei with very low gyromagnetic ratios

Abstract

Chemical shifts and J-couplings are fundamental parameters in NMR spectroscopy as they provide structural information about molecules. Extracting these quantities from isotopes such as carbon or nitrogen results in reduced sensitivity due to their low gyromagnetic ratios. In this work, we present a method for detecting chemical shifts and J-couplings at the microscale in low-gyromagnetic-ratio nuclei using NV centers. By leveraging hydrogen nuclei, we achieve strong coupling with NVs and fast signal emission that aligns with NV coherence times. In addition, the technique is well-suited for implementations under high magnetic fields. We demonstrate that our protocol achieves a sensitivity enhancement of more than one order of magnitude for scenarios involving $^{13}$C, with even greater improvements for nuclei with lower gyromagnetic ratios.