Andreev reflection and 0-π transition in graphene-based antiferromagnetic superconducting junctions

¹ New Energy Technology Engineering Laboratory of Jiangsu Province, School of Science, Nanjing University of Posts and Telecommunications - Nanjing, 210023, China
² College of Physics Science and Technology, Yangzhou University - Yangzhou, 225002, China

^(a) zxf@njupt.edu.cn (corresponding author)
^(b) yfxu@yzu.edu.cn (corresponding author)

Received: 29 November 2018
Accepted: 23 January 2019

Abstract

We investigate the Andreev reflection and 0-π transition in the graphene-based antiferromagnetic superconducting junctions on the SiC substrate, respectively. The differential conductance of Andreev reflection is reduced in the presence of a gap induced by the antiferromagnet or the substrate. Interestingly, although the gap induced by the antiferromagnet is the same to the one induced by the substrate, their differential conductances of the Andreev reflection are absolutely different, which can be used to detect antiferromagnetism in experiment. Although the interaction between the antiferromagnet and the substrate cannot show special differential conductance, their interaction can bring the 0-π transition. This breaks up the conventional wisdom that the antiferromagnetism-induced 0-π transition shows a rigorous atomic-scale dependence on the interlayer thickness. Furthermore, compared with the conventional atomic-scale dependent 0-π transition, our finding can be realized more easily in the experiment.