Specular reflection of polar molecules from a simple multi-cylinder electrostatic mirror: a method for separating BaF molecules produced in a buffer-gas-cooled laser-ablation source from other ablation products

H. -M. Yau; Z. Corriveau; N. T. McCall; J. Perez Garcia; D. Heinrich; R. L. Lambo; G. K. Koyanagi; M. C. George; C. H. Storry; M. Horbatsch; E. A. Hessels

arXiv · 2410.04598

Specular reflection of polar molecules from a simple multi-cylinder electrostatic mirror: a method for separating BaF molecules produced in a buffer-gas-cooled laser-ablation source from other ablation products

H. -M. Yau·Z. Corriveau·N. T. McCall·J. Perez Garcia·D. Heinrich·R. L. Lambo·G. K. Koyanagi·M. C. George·C. H. Storry·M. Horbatsch·E. A. Hessels

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Abstract

A method for specular reflection of polar molecules is proposed. Electrostatatic potentials and forces are calculated for a low-field-seeking molecule near a series of long cylindrical electrodes of radius $r$ with dc potentials of $+V$ and $-V$ applied to alternate electrodes. A center-to-center separation of $2.9\,r$ leads to remarkably flat equipotential surfaces and thus to a nearly planar mirror for specular reflection of the polar molecules, with the angle of reflection equalling the angle of incidence to an accuracy approaching a microradian. This mirror can be used to redirect cryogenic molecular beams. Separating barium monofluoride (BaF) molecules created in a helium-buffer-gas laser-ablation source from other ablation products is a necessary step to producing a pure sample of matrix-isolated BaF, as is required by the EDM$^3$ collaboration for implementing a precise measurement of the electron electric dipole moment. The design and modelling for the BaF deflector based on this electrode geometry is presented.

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H. -M. Yau, Z. Corriveau, N. T. McCall, J. Perez Garcia, D. Heinrich, R. L. Lambo, G. K. Koyanagi, M. C. George, C. H. Storry, M. Horbatsch, E. A. Hessels. 2024-10-06. Specular reflection of polar molecules from a simple multi-cylinder electrostatic mirror: a method for separating BaF molecules produced in a buffer-gas-cooled laser-ablation source from other ablation products. https://arxiv.org/abs/2410.04598

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