Anti-symmetric plasma mode in superconducting films

We consider the propagation of plasma modes in superconducting films bound by a high-dielectric-constant medium and predict a mode that corresponds to the anti-symmetric coupling of the two surface plasmons. We show that anisotropy plays a determinant role in lowering this mode's frequency range, bringing it to the realm of possible experimental observation for the high-T-c superconductors. Theoretical predictions for the maximal and minimum him thickness, where this mode can be found below the plasma frequency along the c-axis, are also made here.