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Non linear conductivity and collective charge excitations in the lowest Landau level

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 نشر من قبل Assa Auerbach
 تاريخ النشر 2016
  مجال البحث فيزياء
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For weakly disordered fractional quantum Hall phases, the non linear photoconductivity is related to the charge susceptibility of the clean system by a Floquet boost. Thus, it may be possible to probe collective charge modes at finite wavevectors by electrical transport. Incompressible phases, irradiated at slightly above the magneto-roton gap, are predicted to exhibit negative photoconductivity and zero resistance states with spontaneous internal electric fields. Non linear conductivity can probe composite fermions charge excitations in compressible filling factors.

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