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arXiv · 2104.04204

Quantum Enhanced Cavity QED Interferometer with Partially Delocalized Atoms in Lattices

Anjun Chu·Peiru He·James K. Thompson·Ana Maria Rey
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Abstract

We propose a quantum enhanced interferometric protocol for gravimetry and force sensing using cold atoms in an optical lattice supported by a standing-wave cavity. By loading the atoms in partially delocalized Wannier-Stark states, it is possible to cancel the undesirable inhomogeneities arising from the mismatch between the lattice and cavity fields and to generate spin squeezed states via a uniform one-axis twisting model. The quantum enhanced sensitivity of the states is combined with the subsequent application of a compound pulse sequence that allows to separate atoms by several lattice sites. This, together with the capability to load small atomic clouds in the lattice at micrometric distances from a surface, make our setup ideal for sensing short-range forces. We show that for arrays of $10^4$ atoms, our protocol can reduce the required averaging time by a factor of $10$ compared to unentangled lattice-based interferometers after accounting for primary sources of decoherence.

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Anjun Chu, Peiru He, James K. Thompson, Ana Maria Rey. 2021-04-09. Quantum Enhanced Cavity QED Interferometer with Partially Delocalized Atoms in Lattices. https://doi.org/10.1103/physrevlett.127.210401

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