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Mechanism for large thermoelectric power in negative-U molecular quantum dots

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 نشر من قبل Theo Costi
 تاريخ النشر 2011
  مجال البحث فيزياء
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We investigate with the aid of numerical renormalization group techniques the thermoelectric properties of a molecular quantum dot described by the negative-U Anderson model. We show that the charge Kondo effect provides a mechanism for enhanced thermoelectric power via a correlation induced asymmetry in the spectral function close to the Fermi level. We show that this effect results in a dramatic enhancement of the Kondo induced peak in the thermopower of negative-U systems with Seebeck coefficients exceeding 50$mu V/K$ over a wide range of gate voltages.

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