|Table of Contents|

Novel 0-π State Transitions in a Superconducting NarrowTwo-Dimensional Topological Insulator Junction(PDF)

《南京师大学报（自然科学版）》[ISSN:1001-4616/CN:32-1239/N]

Issue:
2017年03期
Page:
87-
Research Field:
·物理学·
Publishing date:

Info

Title:
Novel 0-π State Transitions in a Superconducting NarrowTwo-Dimensional Topological Insulator Junction
Author(s):
Yu Qingyun; Tao Yongchun
School of Physics and Technology,Nanjing Normal University,Nanjing 210023,China
Keywords:
narrow two-dimensional topological insulator; interedge coupling; Josephson junction; 0-π state transition
PACS:
O469; O511+.9
DOI:
10.3969/j.issn.1001-4616.2017.03.013
Abstract:
The narrow two-dimensional topological insulator is characterized by the interedge backscattering originating from interedge coupling,which could greatly enrich topological superconducting electronics. Here,considering the interedge coupling,we apply Bogoliubov-de Gennes(BdG)equation to study the Josephson junction composed of a narrow two-dimensional topological insulator strip,where two superconducting electrodes at a distance of d are placed on the same edge of the strip. It is found that varying d could give rise to a 0-π state transition,which in turn can manifest the helical spin texture of the edge states. The mechanism stems from an additional π phase shift caused by the interedge backscattering,being different from the conventional one induced by the length of the ferromagnet sandwiched between two superconducting electrodes. Moreover,an unusually large residual value of the Josephson critical current at the 0-π state transition point is always exhibited. As a result,the results have potential applications in the designs of superconducting electronic devices,for instance,a supercurrent switch with a very efficient performance.

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Last Update: 2017-09-30