Relaxation of Fermionic Excitations in a Strongly Attractive Fermi Gas in an Optical Lattice
CALIFORNIA INST OF TECH PASADENA DEPT OF PHYSICS
Pagination or Media Count:
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-alphaU2tau2InUtau in the large Utau 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.
- Organic Chemistry
- Atomic and Molecular Physics and Spectroscopy
- Nuclear Physics and Elementary Particle Physics