Manipulating the anomalous Josephson effect by interface valley-polarized mixing

¹ Department of Physics and Institute of Theoretical Physics, Nanjing Normal University - Nanjing, China
² Department of Physics, Southeast University - Nanjing 210096, China

^(b) yctao88@163.com
^(c) jwang@seu.edu.cn

Received: 4 April 2019
Accepted: 17 June 2019

Abstract

We theoretically investigate the supercurrent through a Josephson junction with at least one superconducting electrode directly coupled to a valley-polarized graphene sheet. The anomalous Josephson effect is shown and remarkably manipulated by interface valley-polarized mixing together with combination of the static staggered potentials and off-resonant circularly polarized light field inducing the valley polarization. The unconventional Josephson effect results from the breaking of underlying chiral (polarized-valley rotational) and time-reversal symmetries, which in turn shows the equivalence of the valley and spin freedoms. The valley-polarized interface-tunable phase offset will be of great interest in the designing and fabrication of such novel devices based on valleytronics as superconducting flux- and phase-based quantum bits, phase batteries and rectifiers.