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Title: Bose-Fermi Mixtures in a Three-Dimensional Optical Lattice

Abstract

We have studied mixtures of fermionic {sup 40}K and bosonic {sup 87}Rb quantum gases in a three-dimensional optical lattice. We observe that an increasing admixture of the fermionic species diminishes the phase coherence of the bosonic atoms as measured by studying both the visibility of the matter wave interference pattern and the coherence length of the bosons. Moreover, we find that the attractive interactions between bosons and fermions lead to an increase of the boson density in the lattice which we measure by studying three-body recombination in the lattice. In our data, we do not observe three-body loss of the fermionic atoms. An analysis of the thermodynamics of a noninteracting Bose-Fermi mixture in the lattice suggests a mechanism for sympathetic cooling of the fermions in the lattice.

Authors:
; ; ; ;  [1]
  1. Institute of Quantum Electronics, ETH Zuerich, CH-8093 Zurich (Switzerland)
Publication Date:
OSTI Identifier:
20777217
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 18; Other Information: DOI: 10.1103/PhysRevLett.96.180402; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOSE-EINSTEIN CONDENSATION; BOSE-EINSTEIN GAS; BOSONS; COHERENCE LENGTH; COOLING; FERMI GAS; FERMIONS; INTERFERENCE; MIXTURES; POTASSIUM 40; RECOMBINATION; RUBIDIUM 87; THERMODYNAMICS; THREE-BODY PROBLEM; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Guenter, Kenneth, Stoeferle, Thilo, Moritz, Henning, Koehl, Michael, and Esslinger, Tilman. Bose-Fermi Mixtures in a Three-Dimensional Optical Lattice. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.180402.
Guenter, Kenneth, Stoeferle, Thilo, Moritz, Henning, Koehl, Michael, & Esslinger, Tilman. Bose-Fermi Mixtures in a Three-Dimensional Optical Lattice. United States. doi:10.1103/PhysRevLett.96.180402.
Guenter, Kenneth, Stoeferle, Thilo, Moritz, Henning, Koehl, Michael, and Esslinger, Tilman. Fri . "Bose-Fermi Mixtures in a Three-Dimensional Optical Lattice". United States. doi:10.1103/PhysRevLett.96.180402.
@article{osti_20777217,
title = {Bose-Fermi Mixtures in a Three-Dimensional Optical Lattice},
author = {Guenter, Kenneth and Stoeferle, Thilo and Moritz, Henning and Koehl, Michael and Esslinger, Tilman},
abstractNote = {We have studied mixtures of fermionic {sup 40}K and bosonic {sup 87}Rb quantum gases in a three-dimensional optical lattice. We observe that an increasing admixture of the fermionic species diminishes the phase coherence of the bosonic atoms as measured by studying both the visibility of the matter wave interference pattern and the coherence length of the bosons. Moreover, we find that the attractive interactions between bosons and fermions lead to an increase of the boson density in the lattice which we measure by studying three-body recombination in the lattice. In our data, we do not observe three-body loss of the fermionic atoms. An analysis of the thermodynamics of a noninteracting Bose-Fermi mixture in the lattice suggests a mechanism for sympathetic cooling of the fermions in the lattice.},
doi = {10.1103/PhysRevLett.96.180402},
journal = {Physical Review Letters},
number = 18,
volume = 96,
place = {United States},
year = {Fri May 12 00:00:00 EDT 2006},
month = {Fri May 12 00:00:00 EDT 2006}
}
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