title: Liquid-state nuclear spin comagnetometers.
abstract: We discuss nuclear spin comagnetometers based on ultralow-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(-9)  Hz, or about 5×10(-11)  Hz 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.
authors.affiliation: Department of Physics, University of California at Berkeley, Berkeley, California 94720-7300, USA. micah.ledbetter@gmail.com
authors.forename: M P
authors.initials: MP
authors.lastname: Ledbetter
authors.forename: S
authors.initials: S
authors.lastname: Pustelny
authors.forename: D
authors.initials: D
authors.lastname: Budker
authors.forename: M V
authors.initials: MV
authors.lastname: Romalis
authors.forename: J W
authors.initials: JW
authors.lastname: Blanchard
authors.forename: A
authors.initials: A
authors.lastname: Pines