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arXiv · 1012.5924

Linear and nonlinear Stark effect in triangular molecule

Bogdan R. Bulka·Tomasz Kostyrko·Jakub Luczak
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Abstract

We analyze changes of the electronic structure of a triangular molecule under the influence of an electric field (i.e., the Stark effect). The effects of the field are shown to be anisotropic and include both a linear and a nonlinear part. For strong electron correlations, we explicitly derive exchange couplings in an effective spin Hamiltonian. For some conditions one can find a dark spin state, for which one of the spins is decoupled from the others. The model is also applied for studying electronic transport through a system of three coherently coupled quantum dots. Since electron transfer rates are anisotropic, the current characteristics are anisotropic as well, differing for small and large electric field.

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Bogdan R. Bulka, Tomasz Kostyrko, Jakub Luczak. 2011-01-17. Linear and nonlinear Stark effect in triangular molecule. https://doi.org/10.1103/physrevb.83.035301

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