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

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 نشر من قبل Heather Partner
 تاريخ النشر 2009
  مجال البحث فيزياء
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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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