High T(c) superconductor coating: superreflectance and surface waves

For a high T(c) superconductor, a theory is derived that superreflectance (R = 100%) is due to EM field exclusion but is restricted by the energy gap to the far infrared and longer wavelengths. Presence of ohmic dissipation modifies but does not dramatically change the nature of the results. At oblique incidence, EM exclusion leads to surface waves. An ion beam sputtering method is proposed for coating superconductor on cyrstalline substrates. This method has consistently produced near perfect reflectance from optical interference coatings, and holds great potential in producing superreflectance.