Dynamically Polarized SERF Atomic Comagnetometer

TL;DR

This paper introduces a novel dynamically polarized SERF atomic comagnetometer that suppresses technical noise and has the potential to surpass quantum noise limits, enhancing precision in magnetic sensing and fundamental physics experiments.

Contribution

It develops a three-phase evolutionary model for hybrid spin dynamics and demonstrates significant polarization noise suppression in a new K-Rb-$^{21}$Ne SERF comagnetometer.

Findings

Achieved 38.5% suppression of polarization noise.

Established a complete analytical model for hybrid spin ensemble dynamics.

Demonstrated potential to surpass quantum noise limits.

Abstract

Atomic spin sensors are essential for beyond-the-standard-model exploration, biomagnetic measurement, and quantum navigation. While the traditional DC mode spin-exchange relaxation-free (SERF) comagnetometer achieves ultrahigh sensitivity, further improvements require suppressing technical noise and surpassing standard quantum limit. In this work, we develop a K-Rb-$^{21}$Ne SERF atomic comagnetometer that dynamically polarizes the electron and nuclear spins, shielding signals from direct interference by pump light. We establish a three-phase evolutionary model for hybrid spin ensemble dynamics, yielding a complete analytical solution, and analyze the responses to various spin perturbations. Additionally, we achieve an averaged 38.5 $\%$ suppression of the polarization noise and identify the key factors that limit sensitivity improvements. The dynamically polarized comagnetometer exhibits effective suppression of technical noise and holds the potential to overcome quantum noise limit, while offering promising applications in exploring new physics and precise magnetic field measurements.