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Modeling a Schottky-barrier carbon nanotube field-effect transistor with ferromagnetic contacts

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 نشر من قبل Stefan Krompiewski
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف S. Krompiewski




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In this study, a model of a Schottky-barrier carbon nanotube field- effect transistor (CNT-FET), with ferromagnetic contacts, has been developed. The emphasis is put on analysis of current-voltage characteristics as well as shot (and thermal) noise. The method is based on the tight-binding model and the non- equilibrium Greens function technique. The calculations show that, at room temperature, the shot noise of the CNT FET is Poissonian in the sub-threshold region, whereas in elevated gate and drain/source voltage regions the Fano factor gets strongly reduced. Moreover, transport properties strongly depend on relative magnetization orientations in the source and drain contacts. In particular, one observes quite a large tunnel magnetoresistance, whose absolute value may exceed 50%.



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