南京师大学报（自然科学版）2017，Vol.40Issue(3)：87-93,7.DOI:10.3969/j.issn.1001-4616.2017.03.013
狭窄的二维拓扑绝缘体超导结中新奇的0-π态转变
Novel 0-π State Transitions in a Superconducting Narrow Two-Dimensional Topological Insulator Junction
摘要
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-dimen-sional 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 elec-trodes. 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.关键词
狭窄的二维拓扑绝缘体/边间耦合/Josephson结/0-π态转变Key words
narrow two-dimensional topological insulator/interedge coupling/Josephson junction/0-π state transition分类
数理科学引用本文复制引用
俞清云,陶永春..狭窄的二维拓扑绝缘体超导结中新奇的0-π态转变[J].南京师大学报（自然科学版）,2017,40(3):87-93,7.基金项目
江苏省普通高校研究生科研创新计划项目(KYLX161266). （KYLX161266）
