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Title: One-photon-assisted formation of ultracold polar molecules

Abstract

Alkali-metal hydride molecules have large dipole moments in their ground electronic states. We explore the possibility of forming such molecules from a mixture of the ultracold atomic gases, employing a one-photon stimulated radiative association process. Using accurate molecular potential-energy curves and dipole moments, we have calculated the rate coefficients for populating each of the vibrational levels of the X {sup 1}{sigma}{sup +} states of LiH and NaH. We have found that significant molecule formation rates into the upper vibrational levels can be realized with laser intensities and atomic densities that are easily attainable experimentally. We examine the spontaneous emission cascade which takes place from these upper vibrational levels on a time scale of milliseconds, and calculate the resulting rotational populations in v=0. We show that photon emission in the cascade process does not contribute to trap loss and that a large population of molecules in v=0 can be achieved.

Authors:
; ;  [1];  [2]
  1. Physics Department, University of Connecticut, 2152 Hillside Road, Storrs, Connecticut 06269-3046 (United States)
  2. ITAMP, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138 (United States)
Publication Date:
OSTI Identifier:
20787044
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.041403; (c) 2006 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; ALKALI METALS; DENSITY; DIPOLE MOMENTS; GROUND STATES; LASER RADIATION; LITHIUM HYDRIDES; MIXTURES; MOLECULES; PHOTON EMISSION; PHOTON-MOLECULE COLLISIONS; PHOTONS; POTENTIAL ENERGY; REACTION KINETICS; ROTATIONAL STATES; SODIUM HYDRIDES; TRAPS; VIBRATIONAL STATES

Citation Formats

Juarros, Elizabeth, Pellegrini, Philippe, Cote, Robin, and Kirby, Kate. One-photon-assisted formation of ultracold polar molecules. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Juarros, Elizabeth, Pellegrini, Philippe, Cote, Robin, & Kirby, Kate. One-photon-assisted formation of ultracold polar molecules. United States. doi:10.1103/PHYSREVA.73.0.
Juarros, Elizabeth, Pellegrini, Philippe, Cote, Robin, and Kirby, Kate. Sat . "One-photon-assisted formation of ultracold polar molecules". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787044,
title = {One-photon-assisted formation of ultracold polar molecules},
author = {Juarros, Elizabeth and Pellegrini, Philippe and Cote, Robin and Kirby, Kate},
abstractNote = {Alkali-metal hydride molecules have large dipole moments in their ground electronic states. We explore the possibility of forming such molecules from a mixture of the ultracold atomic gases, employing a one-photon stimulated radiative association process. Using accurate molecular potential-energy curves and dipole moments, we have calculated the rate coefficients for populating each of the vibrational levels of the X {sup 1}{sigma}{sup +} states of LiH and NaH. We have found that significant molecule formation rates into the upper vibrational levels can be realized with laser intensities and atomic densities that are easily attainable experimentally. We examine the spontaneous emission cascade which takes place from these upper vibrational levels on a time scale of milliseconds, and calculate the resulting rotational populations in v=0. We show that photon emission in the cascade process does not contribute to trap loss and that a large population of molecules in v=0 can be achieved.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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