Narrowline cooling of dysprosium atoms in an optical tweezer array

TL;DR

This paper demonstrates narrowline cooling of dysprosium atoms in an optical tweezer array, achieving near-ground-state motional control, which advances the manipulation of lanthanide atoms for quantum applications.

Contribution

It introduces a cooling protocol for dysprosium atoms in optical tweezers using a narrow transition and frequency chirping, enabling motional ground state preparation.

Findings

Achieved near-ground-state cooling of dysprosium atoms in optical tweezers.

Demonstrated effective cooling via Raman thermometry.

Prepared an array of 75 atoms close to motional ground state.

Abstract

We perform narrowline cooling of single dysprosium atoms trapped in a 1D optical tweezers array, employing the narrow single-photon transition at 741 nm. At the trapping wavelength of 532 nm, the excited state is less trapped than the ground state. To obtain efficient cooling performances, we chirp the frequency of the cooling beam to subsequently address the red sidebands of different motional states. We demonstrate the effectiveness of the cooling protocol through Raman thermometry, which we characterize for our experimental conditions. We obtain an array of 75 atoms close to the motional ground state in the radial direction of the tweezers. Our results demonstrate the possibility to manipulate the motional degree of freedom of dysprosium in optical tweezers arrays, a key ingredient to exploit the potential of lanthanide-based tweezers platforms for quantum science.