Ramping fermions in optical lattices across a Feshbach resonance release_nxwxgjq35rb4bp7jpsgpajuxzq

by Helmut G. Katzgraber, Aniello Esposito, Matthias Troyer

Released as a article .



We study the properties of ultracold Fermi gases in a three-dimensional optical lattice when crossing a Feshbach resonance. By using a zero-temperature formalism, we show that three-body processes are enhanced in a lattice system in comparison to the continuum case. This poses one possible explanation for the short molecule lifetimes found when decreasing the magnetic field across a Feshbach resonance. Effects of finite temperatures on the molecule formation rates are also discussed by computing the fraction of double-occupied sites. Our results show that current experiments are performed at temperatures considerably higher than expected: lower temperatures are required for fermionic systems to be used to simulate quantum Hamiltonians. In addition, by relating the double occupancy of the lattice to the temperature, we provide a means for thermometry in fermionic lattice systems, previously not accessible experimentally. The effects of ramping a filled lowest band across a Feshbach resonance when increasing the magnetic field are also discussed: fermions are lifted into higher bands due to entanglement of Bloch states, in good agreement with recent experiments.
In text/plain format

Archived Files and Locations

application/pdf  370.3 kB
core.ac.uk (web)
archive.org (archive)
arxiv.org (repository)
web.archive.org (webarchive)
application/pdf  358.1 kB
arxiv.org (repository)
web.archive.org (webarchive)
Read Archived PDF
Type  article
Stage   accepted
Date   2006-10-02
Version   v2
Language   en ?
Work Entity
access all versions, variants, and formats of this works (eg, pre-prints)
Catalog Record
Revision: 01ac8c20-a9f6-4c6f-b98a-bd6421e89f41