We report on the calculation of the fundamental plasmon waveguide modes in linear periodic chains of finite silver nanorods, aligned perpendicular to the chain. The results of rigorous full-electrodynamic calculations by the layer-multiple-scattering method are discussed in conjunction with the results of the widely used coupled-dipole model and a critical evaluation of the latter is provided. More specifically, it is shown that both diameter and height of the nanorods must be much smaller than the interparticle distance; otherwise, for relatively long nanorods close to each other, the coupled-dipole model can fail completely to predict the waveguide dispersion diagram. Moreover, the model systematically underestimates the effect of dissipative losses and cannot describe the effect of a supporting substrate, which is always present in realistic cases and induces considerable changes in the waveguide dispersion diagram.
© 2012 Optical Society of America
Original Manuscript: January 13, 2012
Manuscript Accepted: January 31, 2012
Published: March 30, 2012
Christos Tserkezis and Nikolaos Stefanou, "Calculation of waveguide modes in linear chains of metallic nanorods," J. Opt. Soc. Am. B 29, 827-832 (2012)