Tweezer-assisted subwavelength positioning of atomic arrays in an optical cavity

TL;DR

This paper introduces a precise, tweezer-assisted method for positioning atomic arrays within an optical cavity, significantly improving assembly efficiency and coherence for quantum network applications.

Contribution

The authors demonstrate a novel technique for deterministic atom placement in a cavity, surpassing previous probabilistic methods by four orders of magnitude in efficiency.

Findings

Achieved subwavelength atom positioning accuracy.

Assembled up to seven-atom arrays with high efficiency.

Transferred atoms to a coherent intracavity optical lattice.

Abstract

We present an experimental technique that enables the preparation of defect-free arrays of 87Rb atoms within a microscopic high-finesse optical standing-wave cavity. By employing optical tweezers, we demonstrate atom positioning with a precision well below the cavity wavelength, a crucial requirement for cavity-QED experiments in which maximum atom-cavity coupling strength is required. We leverage our control capabilities to assemble an array of up to seven atoms with an efficiency that exceeds previous probabilistic methods by 4 orders of magnitude. The atoms are subsequently transferred from the tweezer array to a two-dimensional intracavity optical lattice that offers enhanced coherence for spin qubits while maintaining strong atom confinement. Our system overcomes the efficiency limitations of previous probabilistic loading techniques of cavity-coupled atom arrays and opens the path to multiqubit quantum networks with atoms strongly coupled to optical cavities.