Optical detection of NMR J-spectra at zero magnetic field

M. P. Ledbetter; C. W. Crawford; A. Pines; D. E. Wemmer; S. Knappe; J. Kitching; D. Budker

doi:10.1016/j.jmr.2009.03.008

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arXiv · 0901.4069

Optical detection of NMR J-spectra at zero magnetic field

M. P. Ledbetter·C. W. Crawford·A. Pines·D. E. Wemmer·S. Knappe·J. Kitching·D. Budker

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Abstract

Scalar couplings of the form J I_1 \cdot I_2 between nuclei impart valuable information about molecular structure to nuclear magnetic-resonance spectra. Here we demonstrate direct detection of J-spectra due to both heteronuclear and homonuclear J-coupling in a zero-field environment where the Zeeman interaction is completely absent. We show that characteristic functional groups exhibit distinct spectra with straightforward interpretation for chemical identification. Detection is performed with a microfabricated optical atomic magnetometer, providing high sensitivity to samples of microliter volumes. We obtain 0.1 Hz linewidths and measure scalar-coupling parameters with 4-mHz statistical uncertainty. We anticipate that the technique described here will provide a new modality for high-precision "J spectroscopy" using small samples on microchip devices for multiplexed screening, assaying, and sample identification in chemistry and biomedicine.

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M. P. Ledbetter, C. W. Crawford, A. Pines, D. E. Wemmer, S. Knappe, J. Kitching, D. Budker. 2009-01-26. Optical detection of NMR J-spectra at zero magnetic field. https://doi.org/10.1016/j.jmr.2009.03.008

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