Molecular cooling by optical pumping with shaped femtosecond pulses

ORAL

Abstract

Vibrational cooling of translationally cold Cs$_{2}$ molecules into a selected vibrational level v = 0,1,2 or v=7 of the singlet X$^{1}\Sigma _{g}^{+}$ ground electronic state has been realized. Our method is based on repeated optical pumping by laser light with a spectrum broad enough to excite all populated vibrational levels but frequency-shaped in such a way to eliminate transitions from the chosen v level, in which molecules accumulate. Using ultrashort pulse shaping techniques based on Liquid Crystal spatial light modulator a large fraction of the initial molecules is transfered into a single selected vibrational level such as v = 0,1, 2 and 7. Limitations of the method as well as the possible extension to rotational and translational cooling will also be discussed.

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Authors

  • Daniel Comparat

    • Laboratoire Aim\'e Cotton, CNRS, Universit\'e Paris-Sud, B\^at.505, 91405 Orsay, France

  • Dimitris Sofikitis

    • Laboratoire Aim\'e Cotton, CNRS, Universit\'e Paris-Sud, B\^at.505, 91405 Orsay, France

  • Andr\'ea Fioretti

    • Laboratoire Aim\'e Cotton, CNRS, Universit\'e Paris-Sud, B\^at.505, 91405 Orsay, France

  • Xiaolin Li

    • Laboratoire Aim\'e Cotton, CNRS, Universit\'e Paris-Sud, B\^at.505, 91405 Orsay, France

  • Ridha Horchani

    • Laboratoire Aim\'e Cotton, CNRS, Universit\'e Paris-Sud, B\^at.505, 91405 Orsay, France

  • Pierre Pillet

    • Laboratoire Aim\'e Cotton, CNRS, Universit\'e Paris-Sud, B\^at.505, 91405 Orsay, France

  • Maria Allegrini

    • CNISM, Dipartimento di Fisica, Universit\`a di Pisa, Largo Pontecorvo, 3 56127 PISA, Italy

  • Marin Pichler

    • Physics Department, Goucher College, Baltimore, MD 21204, USA

  • Sebastien Weber

    • Laboratoire Collisions, Agr\'egats, R\'eactivit\'e (UMR 5589, CNRS - Universit\'e Paul Sabatier Toulouse 3), IRSAMC, Toulouse, France

  • B\'eatrice Chatel

    • Laboratoire Collisions, Agr\'egats, R\'eactivit\'e (UMR 5589, CNRS - Universit\'e Paul Sabatier Toulouse 3), IRSAMC, Toulouse, France