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arXiv · 1004.3350

NRG for the bosonic single-impurity Anderson model: Dynamics

Hyun-Jung Lee·Krzysztof Byczuk·Ralf Bulla
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Abstract

The bosonic single-impurity Anderson model (B-SIAM) is studied to understand the local dynamics of an atomic quantum dot (AQD) coupled to a Bose-Einstein condensation (BEC) state, which can be implemented to probe the entanglement and the decoherence of a macroscopic condensate. Our recent approach of the numerical renormalization group (NRG) calculation for the B-SIAM revealed a zero-temperature phase diagram, where a Mott phase with local depletion of normal particles is separated from a BEC phase with enhanced density of the condensate. As an extension of the previous work, we present the calculations of the local dynamical quantities of the B-SIAM which reinforce our understanding of the physics in the Mott and the BEC phases.

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Hyun-Jung Lee, Krzysztof Byczuk, Ralf Bulla. 2010-04-20. NRG for the bosonic single-impurity Anderson model: Dynamics. https://doi.org/10.1103/physrevb.82.054516

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