Physical Review Letters

Noble-Gas NMR Detection through Noble-Gas-Rubidium Hyperfine Contact Interaction

B. C. Grover

Published Feb 6, 1978• 177 citations

Abstract

Enhanced noble-gas NMR signals are observed in mixed noble-gas-rubidium samples by monitoring spin polarization of the optically pumped rubidium ensemble mechanized as a magnetometer. These signals are believed to arise through electron exchange enhancement of the contact hyperfine interaction during noble-gas-rubidium binary collisions. Polarization of the noble-gas magnetization is obtained through spin exchange with the rubidium ensemble.

DOI: 10.1103/physrevlett.40.391

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Physical Review Letters

Noble-Gas NMR Detection through Noble-Gas-Rubidium Hyperfine Contact Interaction

B. C. Grover

Published Feb 6, 1978• 177 citations

Publisher

Abstract

DOI: 10.1103/physrevlett.40.391

Related papers

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The spin-exchange rates due to binary collisions and due to the formation of van der Waals molecules between

^{83}\mathrm{Kr}

nuclei and optically pumped rubidium-metal vapor have been determined using a technique that relies on the simultaneous observation of frequency shifts of nuclear magnetic resonance lines of noble-gas atoms and corresponding frequency shifts of electron paramagnetic resonance lines of alkali-metal atoms. In contrast, earlier studies have relied on the observation of the spin-relaxation rate of either the alkali-metal atoms or the noble-gas atoms.

K

and for the nuclear spin

I

of the alkali-metal atom are assumed. Precise formal expressions for spin transfer coefficients are given along with convenient approximations based on a perturbation expansion in powers of ${(\frac{\ensuremath{\alpha}}{\ensuremath{\gamma}N})}^{2}$, a quantity which has been shown to be small by experiment.

{}^{3}\mathrm{He}

system; however, our confidence in the helium results is limited by a lack of knowledge of the interatomic potentials necessary for the calculation.

^{83}\mathrm{Kr}

and

^{129}\mathrm{Xe}

were measured in a vapor of spin-polarized alkali-metal atoms oriented parallel and antiparallel to the external magnetic field. The shift in the EPR frequency of the alkali-metal vapor due to the polarized noble-gas nuclei was measured simultaneously, thus providing a measurement of the absolute noble-gas nuclear polarization. The frequency shifts can be used as a convenient way to measure the absolute nuclear spin polarization of noble gases.