Generation of Motional Squeezed States for Neutral Atoms in Optical Tweezers

TL;DR

This paper presents a simple method to generate and measure motional squeezed states of neutral atoms in optical tweezers, achieving significant squeezing and enabling enhanced control at nanometric precision.

Contribution

It introduces a novel protocol for motional squeezing of neutral atoms in optical tweezers and analyzes the limitations affecting squeezing performance.

Findings

Achieved 5.8 dB of motional squeezing.

Developed a measurement protocol based on momentum spreading.

Identified technical and anharmonicity limits to squeezing.

Abstract

Optical tweezers are a powerful tool for the precise positioning of a variety of small objects, including single neutral atoms. Once trapped, atoms can be cooled to the motional ground state of the tweezers. For a more advanced control of their spatial wavefunction, we report here a simple method to squeeze their motion, and the protocol to measure the squeezing factor based on momentum spreading estimation. We explore the limitations set by the technical imperfections of the tweezers, as well as the more fundamental limit set by their anharmonicity, and finally demonstrate a squeezing of 5.8 dB. The implementation of motional squeezing allows to push back the limit set by the position quantum noise and thus to explore more extreme situations requiring atoms positioned with nanometric precision.