Quantum Enhanced Cavity QED Interferometer with Partially Delocalized Atoms in Lattices

TL;DR

This paper introduces a quantum-enhanced interferometric method using cold atoms in optical lattices to improve gravimetry and force sensing, leveraging spin squeezing and atom separation techniques for higher sensitivity and short-range force detection.

Contribution

It presents a novel protocol combining partial atom delocalization, spin squeezing, and atom separation in optical lattices for enhanced quantum sensing capabilities.

Findings

Reduces averaging time by a factor of 10 with 10,000 atoms.

Enables sensing of short-range forces with micrometric atom-surface distances.

Achieves quantum-enhanced sensitivity through spin squeezing and atom manipulation.

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.