  The possibility to excite Surface Plasmon Polaritons (SPPs) at the interface
between two media depends on the optical properties of both media and
geometrical aspects. Specific conditions allowing the coupling of light with a
plasmon-active interface must be satisfied. Plasmonic effects are well
described in noble metals where the imaginary part of the dielectric
permittivity is often neglected ("perfect medium approximation"). However, some
systems exist for which such approximation cannot be applied, hence requiring a
refinement of the common SPP theory. In this context, several properties of
SPPs such as excitation conditions, period of the electromagnetic field
modulation and SPP lifetime then may strongly deviate from that of the perfect
medium approximation. In this paper, calculations taking into account the
imaginary part of the dielectric permittivities are presented. The model
identifies analytical terms which should not be neglected in the mathematical
description of SPPs on lossy materials. These calculations are applied to
numerous material combinations resulting in a prediction of the corresponding
SPP features. A list of plasmon-active interfaces is provided along with a
quantification of the above mentioned SPP properties in the regime where the
perfect medium approximation is not applicable.
