Current density dependence on phase differences in superconducting tunnel junctions based on two-gap superconductors

Highlights: • The quasiclassical equations in the t-representation for the Green's functions with different arguments are obtained. • The current density expression in terms of the Green's functions in the t-representation is obtained. • The current-phase relation for the superconducting tunnel junctions based on two-gap superconductors is obtained. • The pairing symmetries of the order parameters are analyzed. The quasiclassical equations in the $t$-representation for the matrix Green's functions with different arguments are derived in order to study the superconducting tunnel junctions based on two-gap superconductors. The current density expression in terms of the Green's functions in the $t$-representation are derived. The problem is solved in the framework of the model with the piecewise constant order parameters. The current density through the junction is calculated by taking the boundary conditions for the matrix Green's functions at the junction into account. The obtained analytical expression for the current-phase relation in the two-gap superconductor based tunnel junctions is used to analyze the pairing symmetries of the order parameters.