Effect of symmetry of the electron states of HTSC on the current-voltage characteristics of SIS junctions

The current-voltage $IV$ characteristics of $SIS$ junctions are calculated in the framework of a multiband model with an anisotropic effective order parameter of HTSC. The results of calculations show that the shape of $IV$ characteristic and the density of electron states changes significantly depending on the parameters of the model. A theoretical explanation is proposed for the experimentally observed $s$-like behavior of the $IV$ characteristics of $SIN$ and $SIS$ junctions with BSCCO-type superconductors. The dependence of the superconducting peaks asymmetry on the mutual arrangement of the bands is analyzed. The difference between the obtained results and the results of single-band models with the $s$ and $d$ symmetries of the order parameter is discussed.