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Fractional quantum Hall effect without energy gap

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 نشر من قبل Sergey Murzin
 تاريخ النشر 2006
  مجال البحث فيزياء
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In the fractional quantum Hall effect regime we measure diagonal ($rho_{xx}$) and Hall ($rho_{xy}$) magnetoresistivity tensor components of two-dimensional electron system (2DES) in gated GaAs/Al$_{x}$Ga$_{1-x}$As heterojunctions, together with capacitance between 2DES and the gate. We observe 1/3- and 2/3-fractional quantum Hall effect at rather low magnetic fields where corresponding fractional minima in the thermodynamical density of states have already disappeared manifesting complete suppression of the quasiparticle energy gaps.



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