2D transverse laser cooling of a hexapole focused beam of cold BaF molecules
Abstract
A cryogenic buffer gas beam, an electrostatic hexapole lens, and 2D transverse Doppler laser cooling are combined to produce a bright beam of barium monofluoride (BaF) molecules. Experimental results and trajectory simulations are used to study the laser cooling effect as a function of laser detuning, laser power, laser alignment, and interaction time. A scattering rate of 6.1(1.4) s on the laser cooling transition is obtained; this is of the expected maximum, which is attributed to limited control of the magnetic field used to remix dark states. Using 3 tuneable lasers with appropriate sidebands and detuning, each molecule scatters approximately 400 photons during 2D laser cooling, limited by the interaction time and scattering rate. Leaks to dark states are less than 10. The experimental results are used to benchmark the trajectory simulations to predict the achievable flux 3.5 m downstream for a planned EDM experiment.
Keywords
Cite
@article{arxiv.2506.19069,
title = {2D transverse laser cooling of a hexapole focused beam of cold BaF molecules},
author = {Joost W. F. van Hofslot and Izabella E. Thompson and Anno Touwen and Nithesh Balasubramanian and Roman Bause and Hendrick L. Bethlem and Anastasia Borschevsky and Ties H. Fikkers and Steven Hoekstra and Steven A. Jones and Jelmer E. J. Levenga and Maarten C. Mooij and Heleen Mulder and Bastiaan A. Nijman and Efion H. Prinsen and Bart J. Schellenberg and Lucas van Sloten and Rob G. E. Timmermans and Wim Ubachs and Jordy de Vries and Lorenz Willmann},
journal= {arXiv preprint arXiv:2506.19069},
year = {2025}
}