arXiv:2104.08235 · New Journal of Physics

Characterizing the Zeeman slowing force for 40Ca19F molecules

P. Kaebert, M Stepanova, T Poll, M. Petzold, S Xu, M. Siercke, Silke Ospelkaus

Published Aug 18, 2021• 12 citations

Abstract

Abstract In this paper we investigate the feasibility of Zeeman slowing calcium monofluoride molecules originating from a cryogenic buffer gas cell. We measure the A 2 Π 1 / 2 ( v = 0 , J = 1 2 ) − X 2 Σ 1 / 2 ( v = 0 , N = 1 ) hyperfine spectrum of CaF in the Paschen–Back regime and find excellent agreement with theory. We then investigate the scattering rate of the molecules in a molecular Zeeman slower by illuminating them with light from a 10 mW broad repumper and a 10 mW multi-frequency slowing laser. By comparing our results to theory we can calculate the photon scattering rate at higher powers, leading to a force profile for Zeeman slowing. We show results from a simple 1D simulation demonstrating that this force is narrow enough in velocity space to lead to significant velocity compression, and slowing of the molecules to trappable velocities.

DOI: 10.1088/1367-2630/ac1ed7

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