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Decoupling edge versus bulk conductance in the trivial regime of an InAs/GaSb double quantum well using Corbino ring geometry

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 نشر من قبل Minh Nguyen
 تاريخ النشر 2016
  مجال البحث فيزياء
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A Corbino ring geometry is utilized to analyze edge and bulk conductance of InAs/GaSb quantum well structures. We show that edge conductance exists in the trivial regime of this theoretically-predicted topological system with a temperature insensitive linear resistivity per unit length in the range of 2 kOhm/um. A resistor network model of the device is developed to decouple the edge conductance from the bulk conductance, providing a quantitative technique to further investigate the nature of this trivial edge conductance, conclusively identified here as being of n-type.

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