# A Single-species Atomic Comagnetometer Based on 87Rb atoms

## TL;DR

This paper introduces a novel single-species 87Rb atomic comagnetometer that minimizes systematic errors and achieves competitive sensitivity in testing spin-dependent interactions, with potential for further accuracy improvements.

## Contribution

The paper presents a new comagnetometer design based on 87Rb atoms that reduces systematic errors from magnetic field gradients and demonstrates its capability to constrain spin-dependent gravitational energy.

## Key findings

- Nearly negligible sensitivity to laser power, frequency, and magnetic field variations.
- Measured spin-dependent gravitational energy smaller than 4×10^{-18} eV.
- Potential for further accuracy enhancement through atomic cell optimization.

## Abstract

The comagnetometer has been one of the most sensitive devices with which to test new physics related to spin-dependent interactions, but the comagnetometers based on overlapping ensembles of multiple spin species usually suffer from systematic errors due to magnetic field gradients. Here, we propose a comagnetometer based on the Zeeman transitions of the dual hyperfine levels in ground-state 87Rb atoms, which shows nearly negligible sensitivity to variations of laser power and frequency, magnetic field, and magnetic field gradients. We measured the hypothetical spin-dependent gravitational energy of the proton with the comagnetometer, which is smaller than 4*10^{-18} eV, comparable to the most stringent existing constraint. Through optimization of the atomic cell, it is possible to improve the accuracy of the comagnetometer further.

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Source: https://tomesphere.com/paper/1812.06830