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Andreev reflection adjusting in the multi-terminal device with the kink states

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 نشر من قبل Chao Wang
 تاريخ النشر 2021
  مجال البحث فيزياء
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At the domain wall between two regions with the opposite Chern number, there should be the one-dimensional chiral states, which are called as the kink states. The kink states are robust for the lattice deformations. We design a multi-terminal device with the kink states to study the local Andreev reflection and the crossed Andreev reflection. The coefficient of the crossed Andreev reflection can reach 1 in the four-terminal device. Besides adjusting the phase difference between superconductors, the local Andreev reflection and the crossed Andreev reflection can be controlled by changing the on-site energy and the stagger energy in the four-terminal device. Our results give some new ideas to design the quantum device in the future.



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