Momentum Entanglement for Atom Interferometry

TL;DR

This paper demonstrates a method to generate entangled atoms in different momentum modes from a Bose-Einstein condensate, enhancing the sensitivity of atom interferometers for applications like gravitational wave detection.

Contribution

It introduces a compatible entanglement source for atom interferometers by transferring spin entanglement to momentum modes, achieving significant squeezing.

Findings

Achieved a squeezing parameter of -3.1(8) dB indicating strong entanglement.

Demonstrated transfer of spin entanglement to momentum modes in a BEC.

Enhanced sensitivity potential for quantum gradiometers and gravitational wave detectors.

Abstract

Compared to light interferometers, the flux in cold-atom interferometers is low and the associated shot noise large. Sensitivities beyond these limitations require the preparation of entangled atoms in different momentum modes. Here, we demonstrate a source of entangled atoms that is compatible with state-of-the-art interferometers. Entanglement is transferred from the spin degree of freedom of a Bose-Einstein condensate to well-separated momentum modes, witnessed by a squeezing parameter of -3.1(8) dB. Entanglement-enhanced atom interferometers open up unprecedented sensitivities for quantum gradiometers or gravitational wave detectors.