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Length-dependent Seebeck effect in single-molecule junctions beyond linear response regime

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 نشر من قبل Natalya A. Zimbovskaya
 تاريخ النشر 2017
  مجال البحث فيزياء
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In the present work we theoretically study characteristics of nonlinear Seebeck effect in a single-molecule junction with chain-like bridge of an arbitrary length. We have employed tight-binding models to compute electron transmission trough the system. We concentrate on analysis of dependences of thermovoltage $V_{th} $ and differential thermopower $ S $ on the bridge length. It is shown that $ V_{th} $ becomes stronger and $ S $ grows as the bridge lengthens. We discuss the effects of the bridge coupling to the electrodes and of specific characteristics of terminal sites on the bridge on the length-dependent $ V_{th} $ and $ S $ which appear when the system operates beyond linear response regime.

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