Quasiparticle Green's function theory of the Josephson effect in chiral p-wave superconductor/diffusive normal metal/chiral p-wave superconductor junctions

We study the Josephson effect in chiral p-wave superconductor/diffusive normal metal (DN)/chiral p-wave superconductor (CP/DN/CP) junctions using quasiclassical Green's function formalism with proper boundary conditions. The px+ipy-wave symmetry of superconducting order parameter is chosen which is believed to be the pairing state in Sr2RuO4. We show that the superconducting pair amplitude induced in DN has an odd-frequency spin-triplet s-wave symmetry and is an odd function of Matsubara frequency. Despite the peculiar symmetry properties of the Cooper pairs, the behavior of the Josephson current is rather conventional. We have found that the current-phase relation is almost sinusoidal and the Josephson current is proportional toexp(−L/xi), where xi is the coherence length in DN and L is the thickness of the DN layer. We also calculate the Josephson current in CP/diffusive ferromagnet metal/CP junctions and show that the 0-pi transition can be realized by varying temperature or thickness L similar to the case of conventional s-wave junctions. The obtained results may help to explore the properties of superconducting state in Sr2RuO4.