A supersonic laser ablation beam source with narrow velocity spreads

P Aggarwal; H L Bethlem; A Boeschoten; A Borschevsky; K Esajas; Y Hao; S Hoekstra; K Jungmann; V R Marshall; T B Meijknecht; M C Mooij; R G E Timmermans; A Touwen; W Ubachs; L Willmann; Y Yin; A Zapara

doi:10.1063/5.0035568

A supersonic laser ablation beam source with narrow velocity spreads

Rev Sci Instrum. 2021 Mar 1;92(3):033202. doi: 10.1063/5.0035568.

Authors

P Aggarwal¹, H L Bethlem¹, A Boeschoten¹, A Borschevsky¹, K Esajas¹, Y Hao¹, S Hoekstra¹, K Jungmann¹, V R Marshall¹, T B Meijknecht¹, M C Mooij², R G E Timmermans¹, A Touwen¹, W Ubachs³, L Willmann¹, Y Yin¹, A Zapara¹

Affiliations

¹ Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25 9747AA, The Netherlands.
² Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands.
³ Department of Physics and Astronomy, and LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.

PMID: 33819994
DOI: 10.1063/5.0035568

Abstract

A supersonic beam source for SrF and BaF molecules is constructed by combining the expansion of carrier gas (a mixture of 2% SF₆ and 98% argon) from an Even-Lavie valve with laser ablation of a barium/strontium metal target at a repetition rate of 10 Hz. Molecular beams with a narrow translational velocity spread are produced at relative values of Δv/v = 0.053(11) and 0.054(9) for SrF and BaF, respectively. The relative velocity spread of the beams produced in our source is lower in comparison with the results from other metal fluoride beams produced in supersonic laser ablation sources. The rotational temperature of BaF is measured to be 3.5 K. The source produces 6 × 10⁸ and 10⁷ molecules per steradian per pulse in the X²Σ⁺ (ν = 0, N = 1) state of BaF and SrF molecules, respectively, a state amenable to Stark deceleration and laser cooling.