Phonon resonances in atomic currents through Bose-Fermi mixtures in optical lattices

Journal Article · Fri Oct 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.043617· OSTI ID:21450838

Bruderer, M; Posazhennikova, A; Belzig, W ^[1]; Johnson, T H ^[2]; Clark, S R; Jaksch, D ^[2]

---

1. Fachbereich Physik, Universitaet Konstanz, D-78457 Konstanz (Germany)
2. Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)

We present an analysis of Bose-Fermi mixtures in optical lattices for the case where the lattice potential of the fermions is tilted and the bosons (in the superfluid phase) are described by Bogoliubov phonons. It is shown that the Bogoliubov phonons enable hopping transitions between fermionic Wannier-Stark states; these transitions are accompanied by energy dissipation into the superfluid and result in a net atomic current along the lattice. We derive a general expression for the drift velocity of the fermions and find that the dependence of the atomic current on the lattice tilt exhibits negative differential conductance and phonon resonances. Numerical simulations of the full dynamics of the system based on the time-evolving block decimation algorithm reveal that the phonon resonances should be observable under the conditions of a realistic measuring procedure.

• OSTI ID: 21450838
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 82; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALGORITHMS
BOSONS
COMPUTERIZED SIMULATION
CURRENTS
DISPERSIONS
ENERGY LOSSES
ENERGY-LEVEL TRANSITIONS
FERMIONS
LOSSES
MATHEMATICAL LOGIC
MIXTURES
PHONONS
POTENTIALS
QUASI PARTICLES
RESONANCE
SIMULATION
SUPERFLUIDITY
VELOCITY