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arXiv:cond-mat/0411158 · Physical Review A

Ultracold quantum dynamics: Spin-polarized K+K2 collisions with three identical bosons or fermions

Goulven Quéméner, Pascal Honvault, Jean–Michel Launay, Pavel Soldán, Daniel E. Potter, Jeremy M. Hutson

Published Mar 30, 2005• 83 citations
arXivHTMLPDF

Abstract

We have developed a potential-energy surface for spin-polarized $\mathrm{K}(^{2}S)+{\mathrm{K}}_{2}(^{3}\ensuremath{\Sigma}_{u}^{+})$ collisions and carried out quantum dynamical calculations of vibrational quenching at low and ultralow collision energies for both bosons $^{39}\mathrm{K}$ and $^{41}\mathrm{K}$ and fermions $^{40}\mathrm{K}$. At collision energies above about $0.1\phantom{\rule{0.3em}{0ex}}\mathrm{mK}$ the quenching rates are well described by a classical Langevin model, but at lower energies a fully quantal treatment is essential. We find that for the low initial vibrational state considered here $(v=1)$, the ultracold quenching rates are not substantially suppressed for fermionic atoms. For both bosons and fermions, vibrational quenching is much faster than elastic scattering in the ultralow-temperature regime. This contrasts with the situation found experimentally for molecules formed via Feshbach resonances in very high vibrational states.

DOI
10.1103/physreva.71.032722

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