Entanglement interferometry for precision measurement of atomic scattering properties

TL;DR

This paper demonstrates a two-particle matter wave interferometer with trapped 87Rb atoms, using entanglement dynamics to precisely measure atomic scattering properties and enable non-destructive site separation.

Contribution

It introduces a novel entanglement-based interferometry technique for atomic scattering measurements in optical lattices.

Findings

Achieved high-precision measurement of inter-state scattering length.

Demonstrated non-destructive separation of lattice sites with different atom numbers.

Established entanglement dynamics as a tool for atomic interaction characterization.

Abstract

We report on a two-particle matter wave interferometer realized with pairs of trapped 87Rb atoms. Each pair of atoms is confined at a single site of an optical lattice potential. The interferometer is realized by first creating a coherent spin-mixture of the two atoms and then tuning the inter-state scattering length via a Feshbach resonance. The selective change of the inter-state scattering length leads to an entanglement dynamics of the two-particle state that can be detected in a Ramsey interference experiment. This entanglement dynamics is employed for a precision measurement of atomic interaction parameters. Furthermore, the interferometer allows to separate lattice sites with one or two atoms in a non-destructive way.