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Sequential and co-tunneling behavior in the temperature-dependent thermopower of few-electron quantum dots

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 نشر من قبل Ralf Scheibner
 تاريخ النشر 2006
  مجال البحث فيزياء
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 تأليف R. Scheibner




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We have studied the temperature dependent thermopower of gate-defined, lateral quantum dots in the Coulomb blockade regime using an electron heating technique. The line shape of the thermopower oscillations depends strongly on the contributing tunneling processes. Between 1.5 K and 40 mK a crossover from a pure sawtooth- to an intermitted sawtooth-like line shape is observed. The latter is attributed to the increasing dominance of cotunneling processes in the Coulomb blockade regime at low temperatures.



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