Zero- and Low-Field NMR with Atomic Magnetometers for Chemical Analysis and Imaging

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

With support from the Chemical Measurement and Imaging Program, Profs. Alexander Pines and Dmitry Budker and their groups at the University of California - Berkeley are developing novel methods in chemical analysis based on nuclear magnetic resonance (NMR) spectroscopy of J-coupled systems at zero magnetic-field, using high sensitivity atomic magnetometers to monitor NMR signals. J-couplings are an important parameter in high-field NMR spectroscopy yielding important information about molecular bonding and nuclear spin topology, and are crucial for determination of molecular structure and function. The advantages of using atomic magnetometers to detect such couplings at zero magnetic-field are the high sensitivity of atomic magnetometers to low frequency signals, and the extremely high absolute magnetic field homogeneity, yielding very narrow magnetic resonance lines for high resolution. Major goals include optimization of sensitivity, development of multi-pulse sequences for decoupling and recoupling specific heteronuclear couplings in zero-field multidimensional spectroscopy, investigation of parahydrogen-induced polarization for enhancing signal, and the development of a rudimentary chemical fingerprinting library based on zero field J-spectra. NMR is widely used to characterize materials across nearly all branches of the physical and biological sciences; it is the core of biomedical and other magnetic resonance imaging applications. This fundamental research is expanding the capabilities of NMR by developing and employing new approaches to creating and measuring the associated signals. By advancing the development of sensitive atomic magnetometers, the work will enable portable, low-field magnetic resonance imaging sensors with potential application in a wide variety of fields, ranging from geophysical and space research to medicine to tests of fundamental symmetries. It is providing training to both undergraduate and graduate students in multiple disciplines, as well as mentoring for several postdoctoral researchers.