Surface quality and surface waves on subwavelength-structured silver films
Lezec, H. J.
American Physical Society
We analyze the physical-chemical surface properties of single-slit, single-groove subwavelength-structured silver films with high-resolution transmission electron microscopy and calculate exact solutions to Maxwell’s equations corresponding to recent far-field interferometry experiments using these structures. Contrary to a recent suggestion the surface analysis shows that the silver films are free of detectable contaminants. The finite-difference time-domain calculations, in excellent agreement with experiment, show a rapid fringe amplitude decrease in the near zone (slit-groove distance out to 3–4 wavelengths). Extrapolation to slit-groove distances beyond the near zone shows that the surface wave evolves to the expected bound surface plasmon polariton (SPP). Fourier analysis of these results indicates the presence of a distribution of transient, evanescent modes around the SPP that dephase and dissipate as the surface wave evolves from the near to the far zone.
Finite difference method , Interferometry , Silver , Surface structure , Surface waves , Time domain analysis , Transmission electron microscopy
Gay, G., Alloschery, O., Weiner, J. ,Lezec, H. J. ,O'Dwyer, C. ,Sukharev, M. and Seideman, T. (2007) 'Surface quality and surface waves on subwavelength-structured silver films'. Physical Review E, 75, 016612. http://link.aps.org/doi/10.1103/PhysRevE.75.016612
© 2007 American Physical Society