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From insulator to quantum Hall liquid at low magnetic fields

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 نشر من قبل Chi-Te Liang
 تاريخ النشر 2006
  مجال البحث فيزياء
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We have performed low-temperature transport measurements on a GaAs two-dimensional electron system at low magnetic fields. Multiple temperature-independent points and accompanying oscillations are observed in the longitudinal resistivity between the low-field insulator and the quantum Hall (QH) liquid. Our results support the existence of an intermediate regime, where the amplitudes of magneto-oscillations can be well described by conventional Shubnikov-de Haas theory, between the low-field insulator and QH liquid.



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