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 and JM Geremia

Department of Physics and Astronomy, The University of New Mexico, Albuquerque NM 87313 USA

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.

Funded by: National Science Foundation (PHY-0639994); AFOSR (FA9550-06-01-0178).

Downloads

Resources for the paper include the source document draft history, graphics files, data files, and simulation code used to produce the paper. The document history includes all draft versions, including those submitted and resubmitted to journals, as well as the history of correspondence with the journals. The code makes extensive use of the C++ SDE Integrator classes written by Brad Chase. The zipfile linked below is self-contained, but only includes part of the full sde integration package.

Please follow these links to download the available items in zip format:

• [LaTeX Source and Figure Files] (24MB tar.gz file with RevTeX source and pdf and eps figure files)
• [Simulation Code and Data Files] (63.8 MB tar.gz file with Matlab, mex and C++ source, including pre-compiled mex libraries for 32-bit windows, 64-bit windows, Intel Mac and PowerPC Mac architectures)

We have also provided access to some of the notes we generated during this research project, to provide a glimpse into the project as it progressed. The following archive includes derivations in the form of Mathematica notebooks and laTeX files describing those derivations.

• [Project Notes and Derivations] (tar.gz file containing laTeX source and .nb notebooks)

DISCLAIMER: these notes catalog the path we took toward the results presented in the paper, and therefore also include the history of mistakes and corrections that occurred in the research project. The notes are likely to include typographical errors and mistakes. Please keep that in mind when reading them.