Transport through a nodal surface semimetal-superconductor junction in absence/presence of light irradiation.

Abstract

We study quantum tunneling vias-wave superconductor (SC) junction with a topologically charged nodal surface semimetal (NSSM) where a nonsymmorphic symmetry forces the nodal surfaces to stick to the Brillouin zone boundary. Due to their unique dispersions close to the two dimensional band crossing, the charge carriers in the NSSM display many unorthodox behavior in the nature of Andreev as well as normal reflections at the SC junction interface. We investigate such behaviors for different incident orientations for both subgap and supergap energies where monotonic decays/rises of reflectance with incident energy or angle of incidences are often not followed. We also consider irradiation via light with circular and linear polarization on such systems following a Floquet approach in the limit of high frequency irradiation and probe the stroboscopic temporal evolution of the transport parameters. Our results indicate many nontrivial Andreev transport features including near-depletion of the subgap conductivities. All these nontrivialities can be tested in a cold atom set-up on optical lattices and well experimented for quantum information processing purpose.