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Channel Interference in a Quasi Ballistic Aharonov-Bohm Experiment

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 نشر من قبل Hasselbach
 تاريخ النشر 1997
  مجال البحث فيزياء
والبحث باللغة English
 تأليف G. Cernicchiaro




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New experiments are presented on the transmission of electron waves through a 2DEG (2 dimensional electron gas) ring with a gate on top of one of the branches. Magnetoconductance oscillations are observed, and the phase of the Aharanov-Bohm signal alternates between 0 and pi as the gate voltage is scanned. A Fourier transform of the data reveals a dominant period in the voltage which corresponds to the energy spacing between successive transverse modes.A theoretical model including random phase shifts between successive modes reproduces the essential features of the experiment.



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