Resonant tunneling in superconducting structures with $\mathbf{s}$ and $\mathbf{d}$ symmetry of order parameter

Resonant tunneling processes are studied in superconducting junctions of low transparency with the order parameter of the electrodes of different symmetry. A general equation of the resonant current is derived within the Green's function formalism for the junctions of arbitrary dimensionality. The phase dependence of the supercurrent averaged over the set of localized states is analyzed for superconducting junctions with an isotropic order parameter. A numerical analysis of the resonant current transport in junctions with high-$T_c$ superconducting electrodes with the $d$ symmetry of the order parameter was carried out.