https://doi.org/10.1140/epjd/e2004-00144-9
Photoassociation experiments with ultracold metastable helium
École Normale Supérieure and Collège de France,
Laboratoire Kastler Brossel, 24 rue Lhomond, 75231 Paris Cedex 05,
France
Corresponding author: a leduc@physique.ens.fr
Received:
1
July
2004
Published online:
26
October
2004
The present article gives a review of various
photoassociation (PA) experiments performed at ENS with a gas of
ultracold atoms of metastable helium in the 23S1 state,
using a PA laser beam red-detuned from the 23S1–23P
transitions. Molecular spectra close to the D2 atomic line
(23S
P2) are presented. All the
measured lines are identified as a signature of molecular bound
states having a strong (if not pure) quintet spin character at
short interatomic distance. Close to the D0 atomic line
(23SP0), giant helium dimers can be
produced [see Phys. Rev. Lett. 91, 073203 (2003)]. A laser set-up
improved recently allows us to measure very accurately the binding
energy of the ro-vibrational ground state of the 
purely
long-range potential and the agreement with the theory published
previously is excellent. Finally, preliminary results on 2 photon
PA spectroscopy are given.
PACS: 32.80.Pj – Optical cooling of atoms trapping / 33.20.Kf – Visible molecular spectra / 34.50.Gb – Electronic excitation and ionization of molecules / 34.20.Cf – Interatomic potentials and forces
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004
