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Tunneling between Dilute GaAs Hole Layers

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 نشر من قبل Shashank Misra
 تاريخ النشر 2007
  مجال البحث فيزياء
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We report interlayer tunneling measurements between very dilute two-dimensional GaAs hole layers. Surprisingly, the shape and temperature-dependence of the tunneling spectrum can be explained with a Fermi liquid-based tunneling model, but the peak amplitude is much larger than expected from the available hole band parameters. Data as a function of parallel magnetic field reveal additional anomalous features, including a recurrence of a zero-bias tunneling peak at very large fields. In a perpendicular magnetic field, we observe a robust and narrow tunneling peak at total filling factor $ u_T=1$, signaling the formation of a bilayer quantum Hall ferromagnet.



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