Eur. Phys. J. D 38, 239-247 (2006)
https://doi.org/10.1140/epjd/e2006-00037-y

A high-sensitivity laser-pumped M_x magnetometer

¹ Physics Department, Université de Fribourg, Chemin du Musée 3, 1700 Fribourg, Switzerland
² Paul Scherrer Institute, 5232 Villigen PSI, Switzerland

Corresponding author: ^a Antoine.Weis@unifr.ch

Received: 20 July 2005
Published online: 21 February 2006

Abstract

We discuss the design and performance of a laser-pumped cesium vapor magnetometer in the M_x configuration. The device will be employed in the control and stabilization of fluctuating magnetic fields and gradients in a new experiment searching for a permanent electric dipole moment of the neutron. We have determined the intrinsic sensitivity of the device to be 15 fT in a 1 Hz bandwidth, limited by technical laser noise. In the shot noise limit the magnetometer can reach a sensitivity of 10 fT in a 1 Hz bandwidth. We have used the device to study the fluctuations of a stable magnetic field in a multi-layer magnetic shield for integration times in the range of 2–100 seconds. The residual fluctuations for times up to a few minutes are traced back to the instability of the power supply used to generate the field.