Optical Magnetometry based Current Source

Abstract

We present a current monitoring system based on optical magnetometry, which is able to discriminate true current variations from environmental effects at room temperature. The system consists of a dedicated thermally stable magnetic field confining coil and an array of four optically pumped magnetometers arranged in a two-dimensional gradiometer configuration. These magnetometers monitor magnetic field variations inside the coil, which correlate to the variations of the driving current of the coil. The system uses a digital signal-processing unit to extract and record in real time the magnetic field values measured by the magnetometers, which allows a real time monitoring of the current. The system's coil, which is made out of printed circuit boards, can easily be changed to adapt the current-to-field conversion. Thus, we can expand the applicability of this system to a wide range of currents. By using this system to actively feedback control a current source we stabilized a current of 20 mA on a level better than $5\times 10^{-9}$.

References in corpus (16)

• Optical Magnetometry
• Measurement of the permanent electric dipole moment of the neutron
• A Revised Experimental Upper Limit on the Electric Dipole Moment of the Neutron
• Single-electron current sources: towards a refined definition of ampere
• Portable magnetometry for detection of biomagnetism in ambient environments
• A room temperature 19-channel magnetic field mapping device for cardiac signals
• Ultra-sensitive magnetometry based on free precession of nuclear spins
• Influence of magnetic-field inhomogeneity on nonlinear magneto-optical resonances
• A large sample study of spin relaxation and magnetometric sensitivity of paraffin-coated Cs vapor cells
• Strong suppression of shot noise in a feedback-controlled single-electron transistor
• Wide-bandwidth atomic magnetometry via instantaneous-phase retrieval
• A highly stable atomic vector magnetometer based on free spin precession
• Optically Pumped Cs Magnetometers Enabling a High-Sensitivity Search for the Neutron Electric Dipole Moment
• The n2EDM experiment at the Paul Scherrer Institute
• Demonstration of sensitivity increase in mercury free-spin-precession magnetometers due to laser-based readout for neutron electric dipole moment searches
• PCB Coil Design Producing a Uniform Confined Magnetic Field