Impurity transport through a strongly interacting bosonic quantum gas

Journal Article · Mon Aug 15 04:00:00 EDT 2011 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.84.023617· OSTI ID:22075515

Johnson, T H ^[1]; Clark, S R ^[2]; Bruderer, M ^[3]; Jaksch, D ^[1]

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1. Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)
2. Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore)
3. Fachbereich Physik, Universitaet Konstanz, D-78457 Konstanz (Germany)

Using near-exact numerical simulations, we study the propagation of an impurity through a one-dimensional Bose lattice gas for varying bosonic interaction strengths and filling factors at zero temperature. The impurity is coupled to the Bose gas and confined to a separate tilted lattice. The precise nature of the transport of the impurity is specific to the excitation spectrum of the Bose gas, which allows one to measure properties of the Bose gas nondestructively, in principle, by observing the impurity; here we focus on the spatial and momentum distributions of the impurity as well as its reduced density matrix. For instance, we show it is possible to determine whether the Bose gas is commensurately filled as well as the bandwidth and gap in its excitation spectrum. Moreover, we show that the impurity acts as a witness to the crossover of its environment from the weakly to the strongly interacting regime, i.e., from a superfluid to a Mott insulator or Tonks-Girardeau lattice gas, and the effects on the impurity in both of these strongly interacting regimes are clearly distinguishable. Finally, we find that the spatial coherence of the impurity is related to its propagation through the Bose gas.

• OSTI ID: 22075515
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 2 Vol. 84; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
BOSE-EINSTEIN GAS
COMPUTERIZED SIMULATION
DENSITY MATRIX
EXCITATION
IMPURITIES
ONE-DIMENSIONAL CALCULATIONS
SPECTRA