Dependence on sensitivity patterns of bias fields for vector measurements using optically pumped vapor magnetometers

Abstract

The optical light shift effect is an all-optical technique to create magnetic bias fields to determine the vector components of the magnetic field using a scalar optically pumped magnetometer. We show that the measurement of the induced bias fields is affected by the response pattern of the scalar magnetometer. The sensitivity of the magnetometer affects the minimum total field resolution as well as the angular resolution of the vector measurement. Three configurations of multiple-laser, optically pumped cesium vapor vector magnetometers are characterized for their spatial sensitivity patterns. Each configuration has a unique response level as a function of the relative magnetic field orientation. Thus, the formulations used for angular determination are dependent on the magnetometer configuration, and the angular resolution of the vector measurement is dependent on the relative angle between the magnetic field and the optical probe beam. The spatial dependence of the light shift signals is measured, and the equations describing their responses are presented for each configuration. Equations for determining the field angles from the bias field responses are derived.