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arXiv · 0708.2730

Magnetic Field Estimation at and beyond 1/N Scaling via an Effective Nonlinearity

Bradley A. Chase·Heather L. Partner·Brigette D. Black·Benjamin Q. Baragiola·Robert L. Cook·JM Geremia
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Abstract

We provide evidence, based on direct simulation of the quantum Fisher information, that 1/N scaling of the sensitivity with the number of atoms N in an atomic magnetometer can be surpassed by double-passing a far-detuned laser through the atomic system during Larmor precession. Furthermore, we predict that for N>>1, the proposed double-pass atomic magnetometer can essentially achieve 1/N scaling without requiring any appreciable amount of entanglement.

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Bradley A. Chase, Heather L. Partner, Brigette D. Black, Benjamin Q. Baragiola, Robert L. Cook, JM Geremia. 2009-04-14. Magnetic Field Estimation at and beyond 1/N Scaling via an Effective Nonlinearity. https://arxiv.org/abs/0708.2730

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