All-Optical Nonzero-Field Vector Magnetic Sensor For Magnetoencephalography

Abstract

We present the concept and the results of an investigation of an all-optical vector magnetic field sensor scheme developed for biological applications such as non-zero field magnetoencephalography and magnetocardiography. The scheme differs from the classical two-beam Bell-Bloom scheme in that the detecting laser beam is split into two beams, which are introduced into the cell in orthogonal directions, and the ratio of the amplitudes of the magnetic resonance signals in these beams and their phase difference are measured; strong optical pumping from the lower hyperfine level of the ground state ensures the resonance line narrowing, and detection in two beams is carried out in a balanced schemes by measuring the beam polarization rotation. The proposed sensor is compact, resistant to variations of parameters of laser radiation and highly sensitive to the angle of deflection of the magnetic field vector - with an estimated scalar sensitivity of the order of 16 fT/Hz1/2 in 8x8x8 mm3 cell, an angular sensitivity of 4x10-7 rad, or 0.08'', was demonstrated.

References in corpus (7)

• A 20-Channel Magnetoencephalography System Based on Optically Pumped Magnetometers
• All-Optical Vector Atomic Magnetometer
• Femtotesla direct magnetic gradiometer using a single multipass cell
• An all-optical intrinsic atomic gradiometer with sub-20 fT/cm/$\sqrt{\mathrm{Hz}}$ sensitivity in a 22 $\mu$T earth-scale magnetic field
• A study of scalar optically-pumped magnetometers for use in magnetoencephalography without shielding
• Single-beam all-optical non-zero field magnetometric sensor for magnetoencephalography applications
• Vector Measurements Using All Optical Scalar Atomic Magnetometers

Cited by in corpus (4)

• Accurate vector optically pumped magnetometer with microwave-driven Rabi frequency measurements
• 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
• Ultimate parameters of an all-optical MX resonance in Cs in ultra-weak magnetic field