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Probing Landau quantisation with the presence of insulator-quantum Hall transition in a GaAs two-dimensional electron system

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 نشر من قبل Chi-Te Liang
 تاريخ النشر 2008
  مجال البحث فيزياء
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Magneto-transport measurements are performed on the two-dimensional electron system (2DES) in an AlGaAs/GaAs heterostructure. By increasing the magnetic field perpendicular to the 2DES, magnetoresistivity oscillations due to Landau quantisation can be identified just near the direct insulator-quantum Hall (I-QH) transition. However, different mobilities are obtained from the oscillations and transition point. Our study shows that the direct I-QH transition does not always correspond to the onset of strong localisation.



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