Nonlocal electrodynamic effects in the optical excitation of the surface plasmon resonance

The possible nonlocal electrodynamic effects on the optical excitation of the surface plasmon resonance (SPR) at a metal–dielectric interface are studied theoretically adapting the Kretschmann attenuated-total-reflection (ATR) geometry. Calculations of the SPR reflectivity are performed using both the Lindhard–Mermin and the hydrodynamic models for the dielectric response of the metal film. The results are compared with those obtained from the classical Drude model, as well as those from previous study for a bimetallic system. It is concluded that, unlike the bimetallic system, these nonlocal effects are relatively insignificant in the Kretschmann device, except perhaps at cryogenic temperatures when appreciable changes in dip-reflectivity values can take place due to the significance of single-particle excitation. 2003 Elsevier B.V. All rights reserved.