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Reversible quantum Brownian heat engines for electrons

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 نشر من قبل Heiner Linke
 تاريخ النشر 2002
  مجال البحث فيزياء
والبحث باللغة English
 تأليف T.E. Humphrey




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Brownian heat engines use local temperature gradients in asymmetric potentials to move particles against an external force. The energy efficiency of such machines is generally limited by irreversible heat flow carried by particles that make contact with different heat baths. Here we show that, by using a suitably chosen energy filter, electrons can be transferred reversibly between reservoirs that have different temperatures and electrochemical potentials. We apply this result to propose heat engines based on mesoscopic semiconductor ratchets, which can quasistatically operate arbitrarily close to Carnot efficiency.

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