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arXiv · 0709.3842

A nonlinear Ramsey interferometer operating beyond the Heisenberg limit

S. Choi·B. Sundaram
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Abstract

We show that a dynamically evolving two-mode Bose-Einstein condensate (TBEC) with an adiabatic, time-varying Raman coupling maps exactly onto a nonlinear Ramsey interferometer that includes a nonlinear medium. Assuming a realistic quantum state for the TBEC, namely the SU(2) coherent spin state, we find that the measurement uncertainty of the ``path-difference'' phase shift scales as the standard quantum limit (1/N^{1/2}) where N is the number of atoms, while that for the interatomic scattering strength scales as 1/N^{7/5}, overcoming the Heisenberg limit of 1/N.

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S. Choi, B. Sundaram. 2007-09-24. A nonlinear Ramsey interferometer operating beyond the Heisenberg limit. https://doi.org/10.1103/physreva.77.053613

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