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arXiv · 1106.4779

Magnetocardiography with a modular spin-exchange relaxation free atomic magnetometer array

R Wyllie·M Kauer·G Smetana·R Wakai·T Walker
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Abstract

We present a portable four-channel atomic magnetometer array operating in the spin exchange relaxation-free regime. The magnetometer array has several design features intended to maximize its suitability for biomagnetic measurement, specifically foetal magnetocardiography, such as a compact modular design, and fibre coupled lasers. The modular design allows the independent positioning and orientation of each magnetometer, in principle allowing for non-planar array geometries. Using this array in a magnetically shielded room, we acquire adult magnetocadiograms. These measurements were taken with a 6-11 fT Hz^(-1/2) single-channel baseline sensitivity that is consistent with the independently measured noise level of the magnetically shielded room.

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R Wyllie, M Kauer, G Smetana, R Wakai, T Walker. 2011-10-03. Magnetocardiography with a modular spin-exchange relaxation free atomic magnetometer array. https://doi.org/10.1088/0031-9155%2F57%2F9%2F2619

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