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arXiv · 0811.2705

Coherent shift of localized bound pair in Bose Hubbard model

L. Jin·B. Chen·Z. Song
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Abstract

Based on the exact results obtained by Bethe ansatz, we demonstrate the existence of stable bound pair (BP) wave packet in Bose Hubbard model with arbitrary on-site interaction U. In large-U regime, it is found that an incoming single-particle (SP) can coherently pass through a BP wave packet and leave a coherent shift in the position of it. This suggests a simple scheme for constructing a BP charge qubit to realize a quantum switch, which is capable of controlling the coherent transport of one and only one photon in a one-dimensional waveguide.

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L. Jin, B. Chen, Z. Song. 2008-11-17. Coherent shift of localized bound pair in Bose Hubbard model. https://doi.org/10.1103/physreva.79.032108

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