中国物理B ›› 2022, Vol. 31 ›› Issue (11): 117403-117403.doi: 10.1088/1674-1056/ac7553

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Strain-modulated anisotropic Andreev reflection in a graphene-based superconducting junction

Xingfei Zhou(周兴飞)1,†, Ziming Xu (许子铭)1, Deliang Cao(曹德亮)1, and Fenghua Qi(戚凤华)2,‡   

  1. 1 New Energy Technology Engineering Laboratory of Jiangsu Province, School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China;
    2 School of Electronic Engineering, Nanjing Xiaozhuang University, Nanjing 211171, China
  • 收稿日期:2022-01-26 修回日期:2022-05-20 接受日期:2022-06-02 出版日期:2022-10-17 发布日期:2022-10-19
  • 通讯作者: Xingfei Zhou, Fenghua Qi E-mail:zxf@njupt.edu.cn;qifenghua@njxzc.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 12104232, 11805103, and 11804167), the Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20190137 and BK20180739), the Innovation Research Project of Jiangsu Province, China (Grant No. CZ0070619002), and NJUPT-SF (Grant No. NY218128).

Strain-modulated anisotropic Andreev reflection in a graphene-based superconducting junction

Xingfei Zhou(周兴飞)1,†, Ziming Xu (许子铭)1, Deliang Cao(曹德亮)1, and Fenghua Qi(戚凤华)2,‡   

  1. 1 New Energy Technology Engineering Laboratory of Jiangsu Province, School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210023, China;
    2 School of Electronic Engineering, Nanjing Xiaozhuang University, Nanjing 211171, China
  • Received:2022-01-26 Revised:2022-05-20 Accepted:2022-06-02 Online:2022-10-17 Published:2022-10-19
  • Contact: Xingfei Zhou, Fenghua Qi E-mail:zxf@njupt.edu.cn;qifenghua@njxzc.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 12104232, 11805103, and 11804167), the Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20190137 and BK20180739), the Innovation Research Project of Jiangsu Province, China (Grant No. CZ0070619002), and NJUPT-SF (Grant No. NY218128).

摘要: We investigate the Andreev reflection across a uniaxial strained graphene-based superconducting junction. Compared with pristine graphene-based superconducting junction, three opposite properties are found. Firstly, in the regime of the interband conversion of electron-hole, the Andreev retro-reflection happens. Secondly, in the regime of the intraband conversion of electron-hole, the specular Andreev reflection happens. Thirdly, the perfect Andreev reflection, electron-hole conversion with unit efficiency, happens at a nonzero incident angle of electron. These three exotic properties arise from the strain-induced anisotropic band structure of graphene, which breaks up the original relation between the direction of velocity of particle and the direction of the corresponding wavevector. Our finding gives an insight into the understanding of Andreev reflection and provides an alternative method to modulate the Andreev reflection.

关键词: graphene, uniaxial strain, anisotropic Andreev reflection

Abstract: We investigate the Andreev reflection across a uniaxial strained graphene-based superconducting junction. Compared with pristine graphene-based superconducting junction, three opposite properties are found. Firstly, in the regime of the interband conversion of electron-hole, the Andreev retro-reflection happens. Secondly, in the regime of the intraband conversion of electron-hole, the specular Andreev reflection happens. Thirdly, the perfect Andreev reflection, electron-hole conversion with unit efficiency, happens at a nonzero incident angle of electron. These three exotic properties arise from the strain-induced anisotropic band structure of graphene, which breaks up the original relation between the direction of velocity of particle and the direction of the corresponding wavevector. Our finding gives an insight into the understanding of Andreev reflection and provides an alternative method to modulate the Andreev reflection.

Key words: graphene, uniaxial strain, anisotropic Andreev reflection

中图分类号:  (Proximity effects; Andreev reflection; SN and SNS junctions)

  • 74.45.+c
73.23.Ad (Ballistic transport) 85.25.-j (Superconducting devices)