NONSTATIONARY JOSEPHSON EFFECT AND QUASIPARTICLE TUNNELING BETWEEN PARTIALLY-DIELECTRIZED SUPERCONDUCTORS WITH CHARGE-DENSITY WAVES

The tunnel junctions between superconductors where the Fermi surface (FS) is partially dielectrized are considered. The dielectrization due to Coulomb- and (or) electron-phonon interactions leads to the emergence of the dielectric gap Σ on nested FS sections and the existence of the charge-density waves below temperature T=T d . When T<T c <T d the partially-dielectrized metals become superconductors with a corresponding gap ∆. The voltage dependences of the nonstationary Josephson current and quasiparticle current are calculated for such junctions. The current-voltage (I–V) characteristics involve several Riedel-type singularities and jumps for voltages equal to definite combinations of gaps ∆ and Σ in the fermion excitation spectrum. So, I–V curves are much more complex than the ones for usual BCS-type superconductors. The results for quasiparticle tunneling agree with the experimental data available for oxides.