Laser cooling of barium monofluoride molecules using synthesized optical spectra

TL;DR

This paper demonstrates laser cooling of barium monofluoride molecules using synthesized optical spectra tailored to their hyperfine structure, enabling efficient beam collimation and advancing molecular cooling techniques.

Contribution

The authors develop a method to synthesize tailored optical spectra for laser cooling of complex molecules like 138BaF, improving cooling efficiency and beam control.

Findings

Successful laser cooling and collimation of 138BaF molecules.

Use of synthesized optical spectra to match hyperfine structure.

Potential for applying this technique to other complex molecules.

Abstract

We demonstrate laser cooling of barium monofluoride (138BaF) molecules. We use serrodynes to synthesize time-sequenced optical spectra that can be precisely tailored to the hyperfine structure of this heaviest non-radioactive alkaline earth monofluoride. By optimizing these optical spectra, we realize strong Sisyphus cooling forces that efficiently collimate a molecular beam. Our technique is an important step towards using intense beams of barium monofluoride for precision measurement applications, and will be useful for cooling other molecular species with complex level structure.