A Highly Drift-stable Atomic Magnetometer for Fundamental Physics Experiments

Abstract

We report the design and performance of a non-magnetic drift stable optically pumped cesium magnetometer with a measured sensitivity of 35 fT at 200 s integration time and stability below 50 fT between 70 s and 600 s. To our knowledge this is the most stable magnetic field measurement to date. The sensor is based on the nonlinear magneto-optical rotation effect: in a Bell-Bloom configuration a higher order polarization moment (alignment) of Cs atoms is created with a pump laser beam in an anti-relaxation coated Pyrex cell under vacuum, filled with Cs vapor at room temperature. The polarization plane of light passing through the cell is modulated due the precession of the atoms in an external magnetic field of 2.1 muT, used to optically determine the Larmor precession frequency. Operation is based on a sequence of optical pumping and observation of freely precessing spins at a repetition rate of 8 Hz. This free precession decay readout scheme separates optical pumping and probing and thus ensures a systematically highly clean measurement. Due to the residual offset of the sensor of < 15 pT together with the cross-talk free operation of adjacent sensors, this device is uniquely suitable for a variety of experiments in low-energy particle physics with extreme precision, here as highly stable and systematically clean reference probe in search for time-reversal symmetry violating electric dipole moments.

arXiv commentSubmitted in AIP Applied Physics Letter

References in corpus (8)

• Optical Magnetometry
• Resonant nonlinear magneto-optical effects in atoms
• Electric Dipole Moments of the Atoms, Molecules, Nuclei and Particles
• A Compact, High Performance Atomic Magnetometer for Biomedical Applications
• Relaxation of atomic polarization in paraffin-coated cesium vapor cells
• Ultra-sensitive magnetometry based on free precession of nuclear spins
• A large-scale magnetic shield with 10^6 damping at mHz frequencies
• The PanEDM Neutron Electric Dipole Moment Experiment at the ILL

Cited by in corpus (5)

• How to build a magnetometer with thermal atomic vapor: A tutorial
• Improving Sensitivity of an Amplitude-Modulated Magneto-Optical Atomic Magnetometer using Squeezed Light
• Optically driven spin-alignment precession
• Anomalous suppression of spin-exchange relaxation in alignment signals in cesium in ultra-weak magnetic fields
• Bistability of optical properties of cesium vapor due to collective interaction of alignment and orientation under strong spin exchange conditions