Light-modulated anomalous Andreev reflection in a graphene-based superconducting junction

We investigate the Andreev reflection across a graphene-based superconducting junction irradiated by the linearly polarized off-resonant light. The band structure of graphene is modified by the linearly polarized light, which leads to the anisotropic band structure of graphene. In the coaction of the linearly polarized light and the direction of superconducting junction, three anomalous phenomena, consisting of the Andreev retroreflection (specular Andreev reflection) in the case of interband (intraband) conversion of electron–hole and the nonzero incident angle of perfect Andreev reflection, happen. These three anomalous phenomena arise from the same reason that the relation between wavevector and velocity in the isotropic band structure is broken up in the light-induced anisotropic band structure. Our finding provides an alternative and flexible method to modulate Andreev reflection. Graphical abstract