Quantum phase transitions in the bosonic single-impurity Anderson model

Universität Augsburg, Augsberg, Bavaria, Germany
Physics of Condensed Matter (Impact Factor: 1.35). 07/2006; 56(3):199-203. DOI: 10.1140/epjb/e2007-00118-3
Source: RePEc


We consider a quantum impurity model in which a bosonic impurity
level is coupled to a non-interacting bosonic bath, with the bosons
at the impurity site subject to a local Coulomb repulsion U. Numerical
renormalization group calculations for this bosonic single-impurity
Anderson model reveal a zero-temperature phase diagram where
Mott phases with reduced charge fluctuations are separated from a
Bose-Einstein condensed phase by lines of quantum critical
points. We discuss possible realizations of this model, such as
atomic quantum dots in optical lattices. Furthermore, the bosonic
single-impurity Anderson model appears as an effective impurity model
in a dynamical mean-field theory of the Bose-Hubbard model.

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Available from: Hyun Jung Lee, May 26, 2015
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