Propagating surface plasmon

Kume T, Nakagawa N, Hayashi S et al (1995) Interaction between localized and propagating surface plasmons Ag fine paticles on Al surface. Solid State Commun 93 171-175... 

Figure 5. Normalized propagation constant as a function of angular frequency for a surface plasmon propagating along gold-air interface.

A change in the refractive index at the surface of the metal film gives rise to a change in the propagation constant of a surface plasmon. This change... 

Fig. 9.9 The calculated mode profiles for (a) a surface plasmon mode propagating along a 50 nm thick Au film, with an excitation wavelength of X 800 nm (note the plasmon field amplitude within the Au film is multiplied by 10 for clarity), and (b) a silicon PWEF waveguide with silicon core thickness of 220 nm, for an input wavelength of X 1550 nm...

Incident light can excite a surface plasmon when its x axis component equals the propagation constant for the surface plasmon. SPR occurs when this projected distance matches the wavelength of the surface plasmon (fig. 20). 

J. Ctyroky, J. Homola, M. Skalsky, Modelling of surface plasmon resonance waveguide sensor by complex mode expansion and propagation method, Opt. Quantum Electron. 29, 301-311 (1997). 

Surface plasmon-polaritons (SPP), also referred as to surface plasma waves, are special modes of electromagnetic field which can exist at the interface between a dielectric and a metal that behaves like a nearly-iree electron plasma. A surface plasmon is a transverse-magnetic mode (magnetic vector is perpendicular to the direction of propagation of the wave and parallel to the plane of interface) and is characterized by its propagation constant and field distribution. The propagation constant, P can be expressed as follows ... 

Assuming that the prism has only a minor influence on the propagation constant of the surface plasmon at the interface of a metal and a low refractive index dielectric, the coupling condition can be approximately expressed as follows ... 

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