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Slow relaxation of magnetoresistance in doped p -GaAs/AlGaAs layers with partially filled upper Hubbard band

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 نشر من قبل Agrinskaya
 تاريخ النشر 2008
  مجال البحث فيزياء
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We observed slow relaxation of magnetoresistance in quantum well structures GaAs-AlGaAs with a selective doping of both wells and barrier regions which allowed partial filling of the upper Hubbard band. Such a behavior is explained as related to magnetic-field driven redistribution of the carriers between sites with different occupation numbers due to spin correlation on the doubly occupied centers. This redistribution, in its turn, leads to slow multi-particle relaxations in the Coulomb glass formed by the charged centers.

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