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Topological quantum phase transition and the Berry phase near the Fermi surface in hole-doped quantum wells

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 نشر من قبل Bin Zhou
 تاريخ النشر 2007
  مجال البحث فيزياء
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We propose a topological quantum phase transition for quantum states with different Berry phases in hole-doped III-V semiconductor quantum wells with bulk and structure inversion asymmetry. The Berry phase of the occupied Bloch states can be characteristic of topological metallic states. It is found that the adjustment of thickness of the quantum well may cause a transition of Berry phase in two-dimensional hole gas. Correspondingly, the jump of spin Hall conductivity accompanies the change of the Berry phase. This property is robust against the impurity potentials in the system. Experimental detection of this topological quantum phase transition is discussed.

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