Eur. Phys. J. D 65, 141-149 (2011)
https://doi.org/10.1140/epjd/e2011-10719-x

Regular Article

Prospects for sympathetic cooling of molecules in electrostatic, ac and microwave traps

¹ Centre for Cold Matter, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2AZ, UK
² Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
³ Department of Chemistry, Durham University, South Road, DH1 3 LE Durham, UK

^a e-mail: m.tarbutt@imperial.ac.uk

Received: 22 December 2010
Received in final form: 18 February 2011
Published online: 15 April 2011

Abstract

We consider how trapped molecules can be sympathetically cooled by ultracold atoms. As a prototypical system, we study LiH molecules co-trapped with ultracold Li atoms. We calculate the elastic and inelastic collision cross sections of ⁷LiH + ⁷Li with the molecules initially in the ground state and in the first rotationally excited state. We then use these cross sections to simulate sympathetic cooling in a static electric trap, an ac electric trap, and a microwave trap. In the static trap we find that inelastic losses are too great for cooling to be feasible for this system. The ac and microwave traps confine ground-state molecules, and so inelastic losses are suppressed. However, collisions in the ac trap can take molecules from stable trajectories to unstable ones and so sympathetic cooling is accompanied by trap loss. In the microwave trap there are no such losses and sympathetic cooling should be possible.