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Missing 2k_F Response for Composite Fermions in Phonon Drag

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 نشر من قبل Scott Zelakiewicz
 تاريخ النشر 1999
  مجال البحث فيزياء
والبحث باللغة English
 تأليف S. Zelakiewicz




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The response of composite Fermions to large wavevector scattering has been studied through phonon drag measurements. While the response retains qualitative features of the electron system at zero magnetic field, notable discrepancies develop as the system is varied from a half-filled Landau level by changing density or field. These deviations, which appear to be inconsistent with the current picture of composite Fermions, are absent if half-filling is maintained while changing density. There remains, however, a clear deviation from the temperature dependence anticipated for 2k_F scattering.

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