Correlated charge polarization in a chain of coupled quantum dots

R. Kotlyar; C. A. Stafford; S. Das Sarma

doi:10.1103/physrevb.58.r1746

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arXiv · cond-mat/9709098

Correlated charge polarization in a chain of coupled quantum dots

R. Kotlyar·C. A. Stafford·S. Das Sarma

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Abstract

Coherent charge transfer in a linear array of tunnel-coupled quantum dots, electrostatically coupled to external gates, is investigated using the Bethe ansatz for a symmetrically biased Hubbard chain. Charge polarization in this correlated system is shown to proceed via two distinct processes: formation of bound states in the metallic phase, and charge transfer processes corresponding to a superposition of antibound states at opposite ends of the chain in the Mott-insulating phase. The polarizability in the insulating phase of the chain exhibits a universal scaling behavior, while the polarization charge in the metallic phase of the model is shown to be quantized in units of $e/2$.

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R. Kotlyar, C. A. Stafford, S. Das Sarma. 1997-09-08. Correlated charge polarization in a chain of coupled quantum dots. https://doi.org/10.1103/physrevb.58.r1746

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