Frustrated superconducting junction with tricomponent pairing gap functions

We study a superconducting heterojunction with one side characterized by the unconventional chiral p-wave gap function p(x) +/- ip(y) and the other side the conventional s-wave one. Though a relative phase of +/-pi/2 between any two components of gap functions is favored in the junction region, mutual phase differences cannot achieve +/-pi/2 simultaneously, which results in frustration. Based on a Ginzburg-Landau free-energy analysis, the frustrated pattern is determined to be s + i eta(1)[exp(i eta(2)phi /2)p(x) + eta(3) exp(-i eta(2)phi /2)p(y)] with eta(j) = +/- 1 (j = 1, 2, 3), where phi is the phase difference between the p(x)- and p(y)-wave gap functions. Furthermore, we find that the junction exhibits an anisotropic magnetoelectric effect, manifesting itself as an anisotropic spin magnetization along the edge of the junction.