Response of a Bell–Bloom Magnetometer to a Magnetic Field of Arbitrary Direction

Zhichao Ding,Jie Yuan,Xingwu Long

doi:10.3390/s18051401

Abstract

The Bell–Bloom magnetometer in response to a magnetic field of arbitrary direction is observed theoretically and experimentally. A theoretical model is built from a macroscopic view to simulate the magnetometer frequency response to an external magnetic field of arbitrary direction. Based on the simulation results, the magnetometer characteristics, including the signal phase and amplitude at resonance, the linewidth, and the magnetometer sensitivity, are analyzed, and the dependencies of these characteristics on the external magnetic field direction are obtained, which are verified by the experiment.

Highlights

In order to realize the effective detection of an external magnetic field, many kinds of magnetometers, like the fluxgate [1], Hall probe [2], proton magnetometer [3], soft ferromagnetic dot arrays [4], superconducting quantum interference device (SQUID) [5,6], and atomic magnetometer [7,8], appeared one after another
If the synchronous phase detection is adopted by the Bell–Bloom magnetometer, there may be a great measuring error, since the signal phase varies with the external magnetic field direction
The small the difference of the and 7, we find that the experimental results are in a good agreement with the simulation results, of the signal amplitudes shown in Figure 7a,b comes from the amplitude error of the applied external verifying that the signal phase varies with the external magnetic field direction, and the synchronous magnetic phase fields

Summary

Introduction

In order to realize the effective detection of an external magnetic field, many kinds of magnetometers, like the fluxgate [1], Hall probe [2], proton magnetometer [3], soft ferromagnetic dot arrays [4], superconducting quantum interference device (SQUID) [5,6], and atomic magnetometer [7,8], appeared one after another. When the Bell–Bloom magnetometer is put into practice eventually, in order to choose the proper detection method, the dependency of the signal phase on the external magnetic field direction should be known, and for obtaining a better understanding of the magnetometer performances, like the dead zones and the sensitivity, the dependencies of the signal amplitude and the linewidth on the external magnetic field direction need to be investigated. We choose 133 Cs atoms as the sensory atoms for near room-temperature operation, theoretically and experimentally observing the response of a Bell–Bloom magnetometer to a magnetic field of arbitrary direction

Theory and Simulation

Contour plot ofofthe simulation results ofofψ

Experiment and Results

Conclusions