Eur. Phys. J. D 31, 213-219 (2004)
https://doi.org/10.1140/epjd/e2004-00157-4

Formation of ultracold polar molecules via Raman excitation

¹ Physics Department, University of Connecticut, 2152 Hillside Rd., Storrs, CT 06269-3046, USA
² ITAMP, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA

Corresponding author: ^a eliztj@phys.uconn.edu

Received: 31 August 2004
Published online: 23 November 2004

Abstract

Alkali hydride molecules are very polar, exhibiting large ground-state dipole moments. As ultracold sources of alkali atoms, as well as hydrogen, have been created in the laboratory, we explore theoretically the feasibility of forming such molecules from a mixture of the ultracold atomic gases, employing a two-photon stimulated radiative association process — Raman excitation. Using accurate molecular potential energy curves and dipole transition moments, we have calculated the rate coefficients for populating all the vibrational levels of the X state of LiH via the excited A state. We have found that significant molecule formation rates can be realized with laser intensities and atomic densities that are attainable experimentally. Because of the large X state dipole moment, rapid cascade occurs down the ladder of vibrational levels to v=0. The calculated recoil momentum imparted to the molecule is small, and thus negligible trap loss results from the cascade process. This allows for the build-up of a large population of v=0 trapped molecules.