Relaxation of Fermionic Excitations in a Strongly Attractive Fermi Gas in an Optical Lattice
Abstract
We theoretically study the relaxation of high energy single particle excitations into molecules in a system of attractive fermions in an optical lattice, both in the superfluid and the normal phase. In a system characterized by an interaction scale U and a tunneling rate tau, we show that the relaxation rate scales as approximately Ctexp[-alphaU(2)/tau(2)In(U/tau)] in the large U/tau limit. We obtain explicit expressions for the temperature and density dependent exponent alpha, both in the low temperature superfluid phase and the high temperature phase with pairing but no coherence between the molecules. We find that the relaxation rate decreases both with temperature and deviation of the fermion density from half filling. We show that quasiparticle and phase degrees of freedom are effectively decoupled within experimental time scales allowing for observation of ordered states even at high total energy of the system.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 27, 2011
- Accession Number
- ADA555854
Entities
People
- Ana M. Rey
- David Pekker
- Eugene A. Demler
- Mikhail Lukin
- Rajdeep Sensarma
Organizations
- California Institute of Technology