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Title: Fine and hyperfine interactions in cold YbF-He collisions in electromagnetic fields

Abstract

We present a rigorous study of cold and ultracold collisions of YbF({sup 2}{sigma}) molecules with He atoms in external electric and magnetic fields based on an accurate calculation of the interaction potential surface and quantum theory of atom-molecule scattering. We analyze the mechanisms of collisional depolarization of the electron and nuclear spins of YbF and demonstrate that the rate constants for elastic and inelastic collisions of YbF with He are sensitive to the magnitudes of the applied fields. Collisions of heavy polar molecules like YbF may thus be easily manipulated with external electromagnetic fields. We show that collisional spin relaxation of YbF molecules in rotationally excited states is suppressed by electric fields much more significantly than the spin relaxation in the ground rotational state. We explain this by the influence of electric-field-induced Feshbach resonances, which occur at much lower collision energies when the molecule is rotationally excited. Our results suggest that heavy polar molecules may be amenable to magnetic trapping in a buffer gas of He, which could greatly enhance the sensitivity of spectroscopic experiments to measure the electric dipole moment of the electron.

Authors:
;  [1];  [2];  [3];  [4]
  1. Department of Chemistry, University of British Columbia, Vancouver, B.C., Canada V6T 1Z1 (Canada)
  2. Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742-2021 (United States)
  3. Department of Chemistry, Oakland University, Rochester, Michigan 48309 (United States)
  4. (Poland)
Publication Date:
OSTI Identifier:
20982364
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.033416; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; DEPOLARIZATION; ELECTRIC DIPOLE MOMENTS; ELECTRIC FIELDS; ELECTROMAGNETIC FIELDS; ELECTRONS; FINE STRUCTURE; FLUORINE COMPOUNDS; GROUND STATES; HELIUM; HYPERFINE STRUCTURE; INTERACTIONS; MAGNETIC FIELDS; MOLECULE-MOLECULE COLLISIONS; MOLECULES; POTENTIALS; RESONANCE; ROTATIONAL STATES; SPIN; TRAPPING; YTTERBIUM COMPOUNDS

Citation Formats

Tscherbul, T. V., Krems, R. V., Klos, J., Rajchel, L., and Faculty of Chemistry, Warsaw University, Pasteura 1, 03-093 Warszawa. Fine and hyperfine interactions in cold YbF-He collisions in electromagnetic fields. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.033416.
Tscherbul, T. V., Krems, R. V., Klos, J., Rajchel, L., & Faculty of Chemistry, Warsaw University, Pasteura 1, 03-093 Warszawa. Fine and hyperfine interactions in cold YbF-He collisions in electromagnetic fields. United States. doi:10.1103/PHYSREVA.75.033416.
Tscherbul, T. V., Krems, R. V., Klos, J., Rajchel, L., and Faculty of Chemistry, Warsaw University, Pasteura 1, 03-093 Warszawa. Thu . "Fine and hyperfine interactions in cold YbF-He collisions in electromagnetic fields". United States. doi:10.1103/PHYSREVA.75.033416.
@article{osti_20982364,
title = {Fine and hyperfine interactions in cold YbF-He collisions in electromagnetic fields},
author = {Tscherbul, T. V. and Krems, R. V. and Klos, J. and Rajchel, L. and Faculty of Chemistry, Warsaw University, Pasteura 1, 03-093 Warszawa},
abstractNote = {We present a rigorous study of cold and ultracold collisions of YbF({sup 2}{sigma}) molecules with He atoms in external electric and magnetic fields based on an accurate calculation of the interaction potential surface and quantum theory of atom-molecule scattering. We analyze the mechanisms of collisional depolarization of the electron and nuclear spins of YbF and demonstrate that the rate constants for elastic and inelastic collisions of YbF with He are sensitive to the magnitudes of the applied fields. Collisions of heavy polar molecules like YbF may thus be easily manipulated with external electromagnetic fields. We show that collisional spin relaxation of YbF molecules in rotationally excited states is suppressed by electric fields much more significantly than the spin relaxation in the ground rotational state. We explain this by the influence of electric-field-induced Feshbach resonances, which occur at much lower collision energies when the molecule is rotationally excited. Our results suggest that heavy polar molecules may be amenable to magnetic trapping in a buffer gas of He, which could greatly enhance the sensitivity of spectroscopic experiments to measure the electric dipole moment of the electron.},
doi = {10.1103/PHYSREVA.75.033416},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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