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تسجيل مستخدم جديدElectronic thermal conductivity in 2D topological insulator in a HgTe quantum well
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We have measured the differential resistance in a two-dimensional topological insulator (2DTI) in a HgTe quantum well, as a function of the applied dc current. The transport near the charge neutrality point is characterized by a pair of counter propagating gapless edge modes. In the presence of an electric field, the energy is transported by counter propagating channels in the opposite direction. We test a hot carrier effect model and demonstrate that the energy transfer complies with the Wiedemann Franz law near the charge neutrality point in the edge transport regime.
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The two-dimensional topological insulator phase has been observed previously in single HgTe-based quantum wells with inverted subband ordering. In double quantum wells (DQWs), coupling between the layers introduces additional degrees of freedom leadi
ng to a rich phase picture. By studying local and nonlocal resistance in HgTe-based DQWs, we observe both the gapless semimetal phase and the topological insulator phase, depending on parameters of the samples and according to theoretical predictions. Our work establishes the DQWs as a promising platform for realization of multilayer topological insulators.
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The results of experimental study of interference induced magnetoconductivity in narrow quantum well HgTe with the normal energy spectrum are presented. Analysis is performed with taking into account the conductivity anisotropy. It is shown that the
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