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Magnetic barrier induced conductance fluctuations in quantum wires

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 نشر من قبل Thomas Heinzel
 تاريخ النشر 2008
  مجال البحث فيزياء
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Quasi-ballistic semiconductor quantum wires are exposed to localized perpendicular magnetic fields, also known as magnetic barriers. Pronounced, reproducible conductance fluctuations as a function of the magnetic barrier amplitude are observed. The fluctuations are strongly temperature dependent and remain visible up to temperatures of about 10 K. Simulations based on recursive Green functions suggest that the conductance fluctuations originate from parametric interferences of the electronic wave functions which experience scattering between the magnetic barrier and the electrostatic potential landscape.



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