[Spectroscopie par photoassociation d'atomes ultra-froids de molécules de grande élongation]
La spectroscopie des molécules dites « de grande élongation », pour lesquelles la distance interatomique est considérablement plus grande qu'elle ne l'est habituellement dans la liaison chimique peut être réalisée par photoassociation d'atomes ultra-froids. Nous présentons ici une synthèse des résultats obtenus par spectroscopie de photoassociation à un et à deux photons pour la molécules de Cs2. Les potentiels excités concernés sont les potentiels 0g− et 1u, corrélés à la limite asymptotique (6s+6p3/2). Tous les résultats obtenus ont été interprétés dans une approche théorique asymptotique, spécialement développée pour l'étude de ces molécules de grande élongation.
Spectroscopic study of so-called long-range molecules, with average interatomic distances much larger than usual for chemical bonds, is conveniently performed by photoassociation (PA) of ultracold atoms. We present here a review of our results obtained by one and two-photon PA spectroscopy of the Cs2 molecule, using as intermediate the 0g− and 1u potentials correlated to the (6s+6p3/2) asymptote. These results have been interpreted using an asymptotic theoretical approach, which was specifically build for such long-range molecules.
Mot clés : Photoassociation, Refroidissement laser, Piégeage d'atomes, Spectroscopie, Potentiel asymptotique, Molécules de grande élongation, Césium, Structure hyperfine
Nicolas Vanhaecke 1 ; Daniel Comparat 1 ; Anne Crubellier 1 ; Pierre Pillet 1
@article{CRPHYS_2004__5_2_161_0, author = {Nicolas Vanhaecke and Daniel Comparat and Anne Crubellier and Pierre Pillet}, title = {Photoassociation spectroscopy of ultra-cold long-range molecules}, journal = {Comptes Rendus. Physique}, pages = {161--169}, publisher = {Elsevier}, volume = {5}, number = {2}, year = {2004}, doi = {10.1016/j.crhy.2004.01.018}, language = {en}, }
TY - JOUR AU - Nicolas Vanhaecke AU - Daniel Comparat AU - Anne Crubellier AU - Pierre Pillet TI - Photoassociation spectroscopy of ultra-cold long-range molecules JO - Comptes Rendus. Physique PY - 2004 SP - 161 EP - 169 VL - 5 IS - 2 PB - Elsevier DO - 10.1016/j.crhy.2004.01.018 LA - en ID - CRPHYS_2004__5_2_161_0 ER -
Nicolas Vanhaecke; Daniel Comparat; Anne Crubellier; Pierre Pillet. Photoassociation spectroscopy of ultra-cold long-range molecules. Comptes Rendus. Physique, Volume 5 (2004) no. 2, pp. 161-169. doi : 10.1016/j.crhy.2004.01.018. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2004.01.018/
[1] Laser-induced photoassociation of ultracold sodium atoms, Phys. Rev. Lett., Volume 58 (1987), p. 2420
[2] Experiments and theory in cold and ultracold collisions, Rev. Mod. Phys., Volume 71 (1999), p. 1
[3] Photoassociation of ultracold atoms: a new spectroscopic technique, J. Mol. Spectrosc., Volume 195 (1999), p. 194
[4] Spectroscopy of Na2 by photoassociation of laser-cooled Na, Phys. Rev. Lett., Volume 71 (1993), p. 2200
[5] Photoassociation spectrum of ultracold Rb atoms, Phys. Rev. Lett., Volume 71 (1993), p. 2204
[6] Spectroscopic determination of the s-wave scattering length of lithium, Phys. Rev. Lett., Volume 74 (1995), p. 1315
[7] Photoassociative spectroscopy of ultracold 39K atoms in a high density vapor-cell magneto-optical trap, Phys. Rev. A, Volume 53 (1996), p. R1216
[8] Formation of Cs2 cold molecules through photoassociation, Phys. Rev. Lett., Volume 80 (1998), p. 4402
[9] Photoassociation of spin-polarized hydrogen, Phys. Rev. Lett., Volume 82 (1999), p. 307
[10] Photoassociation spectroscopy of cold He(23s) atoms, Phys. Rev. Lett., Volume 84 (2000), p. 1874
[11] Giant helium dimers produced by photoassociation of ultracold metastable atoms, Phys. Rev. Lett., Volume 91 (2003), p. 073203
[12] Photoassociation of cold Ca atoms, Phys. Rev. Lett., Volume 85 (2000) no. 11, p. 2292
[13] Photoassociative ionization of heteronuclear molecules in a novel two-species magneto-optical trap, Phys. Rev. Lett., Volume 82 (1999) no. 6, p. 1124
[14] Photoassociation of heteronuclear lithium, Appl. Phys. B, Volume 73 (2001), p. 801
[15] Production of ultracold polar RbCs∗ molecules via photoassociation, Phys. Rev. Lett., Volume 92 (2004), p. 033004
[16] Efficient production of ground state potassium molecules at sub-mK temperatures by two-step photoassociation, Phys. Rev. Lett., Volume 84 (2000), p. 246
[17] Two-color photoassociation spectroscopy of ground state Rb2, Phys. Rev. Lett., Volume 79 (1997), p. 1245
[18] Observation of cold state-selected cesium molecules formed by stimulated Raman photoassociation, Phys. Rev. A, Volume 64 (2001), p. 61401(R)
[19] Semianalytic theory of laser-assisted cold collisions, Phys. Rev. A, Volume 60 (1999) no. 1, p. 414
[20] Line shape analysis of two-colour photoassociation spectra on the example of the Cs2 ground state, Eur. Phys. J. D, Volume 21 (2002), pp. 299-309
[21] Pure long-range molecules, Phys. Rev. Lett., Volume 195 (1978), pp. 194-228
[22] Photoassociation in a gas of cold alkali atoms. I: Perturbative quantum approach, J. Phys. B, Volume 30 (1997), p. 2801
[23] Mechanism for the production of vibrationally excited ultracold molecules of 7Li2, Chem. Phys. Lett., Volume 279 (1997), p. 50
[24] Experimental versus theoretical rates for photoassociation and for formation of ultracold molecules, IEEE J. Quant. Electron., Volume 36 (2000), p. 1378
[25] Photoassociative spectroscopy as a self-sufficient tool for the determination of the cs triplet scattering length, Phys. Rev. Lett., Volume 85 (2000), p. 1408
[26] Expectation values of the kinetic and potential energy of a diatomic molecule, J. Chem. Phys., Volume 58 (1973), p. 3867
[27] Dissociation energy and long-range potential of diatomic molecules from vibrational spacings of higher levels, J. Chem. Phys., Volume 52 (1970), p. 3869
[28] Improved LeRoy–Bernstein near-dissociation expansion formula, and prospect for photoassociation spectroscopy, J. Chem. Phys., Volume 120 (2004), p. 1318
[29] Photoassociative spectroscopy of the Cs long-range state, Eur. Phys. J. D, Volume 5 (1999), p. 389
[30] Determination of the Cs(p3/2) potential curve and the Cs 6p1/2,3/2 atomic radiative lifetimes grom photoassociation spectroscopy, Phys. Rev. A, Volume 66 (2002), p. 052506
[31] A spectroscopic determination of scattering lengths for sodium atom collisions, J. Res. Inst. Stand. Technol., Volume 101 (1996), p. 505
[32] Formation of cold Cs2 ground state molecules through photoassociation of the 1u long-range state, Eur. Phys. J. D, Volume 11 (2000), p. 59
[33] Analytical interaction potentials of the long range alkali-metal dimers, Z. Phys. D, Volume 36 (1996), pp. 239-248
[34] Hyperfine interaction between the singlet and triplet ground states of Cs2: a textbook example of gerade-ungerade symmetry breaking, Chem. Phys. Lett., Volume 124 (1986) no. 4, p. 470
[35] N. Vanhaecke, Ch. Lisdat, B.T'Jampens, D. Comparat, A. Crubelleier, P. Pillet, Accurate asymptotic ground state potential curves of Cs2 from two-colour photoassociation, Eur. Phys. J. D (2004), in press
[36] Coupled singlet-triplet analysis of two-color cold-atom photoassociation spectra, Phys. Rev. A, Volume 61 (2000), p. 043407
[37] Simple determination of Na2 scattering lengths using observed bound levels at the ground state asymptote, Eur. Phys. J. D, Volume 6 (1999), pp. 211-220
[38] Molecules in a Bose–Einstein condensate, Science, Volume 287 (2000), p. 1016
[39] N. Spiess, Ph.D. thesis, Fachbereich Chemie, Universität Kaiserslautern, 1989
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