We discuss nuclear spin comagnetometers based on ultra-low-field nuclear magnetic resonance in mixtures of miscible solvents, each rich in a different nuclear spin. In one version thereof, Larmor precession of protons and 19F nuclei in a mixture of thermally polarized pentane and hexafluorobenzene is monitored via a sensitive alkali-vapor magnetometer. We realize transverse relaxation times in excess of 20 s and suppression of magnetic field fluctuations by a factor of 3400. We estimate it should be possible to achieve single-shot sensitivity of about 5×10−9Hz, or about 5×10−11Hz in ≈1 day of integration. In a second version, spin precession of protons and 129Xe nuclei in a mixture of pentane and hyperpolarized liquid xenon is monitored using superconducting quantum interference devices. Application to spin-gravity experiments, electric dipole moment experiments, and sensitive gyroscopes is discussed.
@article{arxiv.1201.4438,
title = {Liquid-state nuclear spin comagnetometers},
author = {Micah Ledbetter and Szymon Pustelny and Dmitry Budker and Michael Romalis and John Blanchard and Alexander Pines},
journal= {arXiv preprint arXiv:1201.4438},
year = {2013}
}