Ultracold homonuclear and heteronuclear collisions in metastable helium

Abstract

Scattering and ionizing cross sections and rates are calculated for ultracold collisions between metastable helium atoms using a fully quantum-mechanical close-coupled formalism. Homonuclear collisions of the bosonic ${}^4$He${}^{\ast }+{}^4$He${}^{\ast }$ and fermionic ${}^3$He${}^{\ast }+{}^3$He${}^{\ast }$ systems, and heteronuclear collisions of the mixed ${}^3$He${}^{\ast }+{}^4$He${}^{\ast }$ system, are investigated over a temperature range 1 $\mu$K to 1 K. Carefully constructed Born-Oppenheimer molecular potentials are used to describe the electrostatic interaction between the colliding atoms, and complex optical potentials used to represent loss through ionization from the ${}^{1,3}\Sigma$ states. Magnetic spin-dipole mediated transitions from the ${}^5\Sigma$ state are included and results reported for spin-polarized and unpolarized systems. Comparisons are made with experimental results, previous semi-classical models, and a perturbed single channel model.

14 pages, 9 figures

References in corpus (8)

• Many-Body Physics with Ultracold Gases
• Camparison of the Hanbury Brown-Twiss effect for bosons and fermions
• Ghost Imaging with Atoms
• Homonuclear ionizing collisions of laser-cooled metastable helium atoms
• Heteronuclear ionizing collisions between laser-cooled metastable helium atoms
• Spin-dipole induced lifetime of the least-bound quintet sigma state of He(2S)+He(2S)
• Autoionization of spin-polarized metastable helium in tight anisotropic harmonic traps
• Long-range states in excited ultracold 3He*-4He* dimers

Cited by in corpus (1)

• Close-coupled model of Feshbach resonances in ultracold ${}^3$He* and ${}^4$He* atomic Collisions