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Manifestation of the bulk phase transition in the edge energy spectrum in a two dimensional bilayer electron system

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 نشر من قبل Eduard V. Deviatov
 تاريخ النشر 2004
  مجال البحث فيزياء
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We use a quasi-Corbino sample geometry with independent contacts to different edge states in the quantum Hall effect regime to investigate the edge energy spectrum of a bilayer electron system at total filling factor $ u=2$. By analyzing non-linear $I-V$ curves in normal and tilted magnetic fields we conclude that the edge energy spectrum is in a close connection with the bulk one. At the bulk phase transition spin-singlet - canted antiferromagnetic phase $I-V$ curve becomes to be linear, indicating the disappearance or strong narrowing of the $ u=1$ incompressible strip at the edge of the sample.



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