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Physical Review Applied

Simultaneous Determination of the Spin Polarizations of Noble-Gas and Alkali-Metal Atoms Based on the Dynamics of the Spin Ensembles

Kai Wei, Tian Zhao, Xiujie Fang, Hairong Li, Yueyang Zhai, Bangcheng Han, Wei Quan

Published Apr 10, 2020• 41 citations
Publisher

Abstract

We demonstrate a method for simultaneously measuring the spin polarizations of noble-gas and alkali-metal atoms. Under a low magnetic field, the polarized alkali-metal and noble-gas spin ensembles exhibit novel dynamics in the self-compensation and resonance regimes, which can be used to measure the polarizations. We perform this method on a $\mathrm{K}$-$\mathrm{Rb}$-${}^{21}$$\mathrm{Ne}$ comagnetometer with various operation temperatures and pump-light intensities. The polarization of alkali-metal electrons from 0.245 to 0.964 and the polarization of noble-gas nuclear spins from 0.01 to 0.065 are measured with relative uncertainties less than $12.4\mathrm{%}$. The measured polarizations are consistent with the theoretical model and are also verified by the traditional polarization-measurement method.

DOI
10.1103/physrevapplied.13.044027

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