Characterizing atomic magnetic gradiometers for fetal magnetocardiography

Abstract

Atomic magnetometers (AMs) offer many advantages over superconducting quantum interference devices (SQUIDs) due to, among other things, having comparable sensitivity while not requiring cryogenics. One of the major limitations of AMs is the challenge of configuring them as gradiometers. We report the development of a spin-exchange relaxation free (SERF) vector atomic magnetic gradiometer with sensitivity of $3\mathrm{fT}{\mathrm{cm}}^{-1}{\mathrm{Hz}}^{-1/2}$ and common mode rejection ratio (CMRR) $>150$ in the band from DC to 100 Hz. We introduce a background suppression figure of merit for characterizing the performance of gradiometers. It allows for optimally setting the measurement baseline, and for quickly assessing the advantage, if any, of performing a measurement in gradiometric mode. As an application, we consider the problem of fetal magnetocardiography (fMCG) detection in the presence of a large background maternal MCG signal.

References in corpus (9)

• Ultra-high sensitivity magnetic field and magnetization measurements with an atomic magnetometer
• Sub-femtotesla scalar atomic magnetometer using multipass cells
• A room temperature 19-channel magnetic field mapping device for cardiac signals
• A microfabricated optically-pumped magnetic gradiometer
• Optical Magnetometer Array for Fetal Magnetocardiography
• Magnetocardiography with a modular spin-exchange relaxation free atomic magnetometer array
• Diffusive Suppression of AC-Stark Shifts in Atomic Magnetometers
• Magnetic Gradiometer for Detection of Zero- and Ultralow-Field Nuclear Magnetic Resonance
• Design and performance of an absolute ${}^3$He/Cs magnetometer

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• A single beam Cs-Ne SERF magnetometer with differential laser power noise suppression method