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Tunable Negative Differential Resistance controlled by Spin Blockade in Single Electron Transistors

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 نشر من قبل Mariusz Ciorga
 تاريخ النشر 2001
  مجال البحث فيزياء
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We demonstrate a tunable negative differential resistance controlled by spin blockade in single electron transistors. The single electron transistors containing a few electrons and spin polarized source and drain contacts were formed in GaAs/GaAlAs heterojunctions using metallic gates. Coulomb blockade measurements performed as a function of applied source-drain bias, electron number and magnetic field reveal well defined regimes where a decrease in the current is observed with increasing bias. We establish that the origin of the negative differential regime is the spin-polarized detection of electrons combined with a long spin relaxation time in the dot. These results indicate new functionalities that may be utilized in nano-spintronic devices in which the spin state is electro-statically controlled via the electron occupation number.

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