Plasmon oscillations in a linear cluster of spherical nanoparticles

The eigenfrequencies and eigenfunctions of plasmon oscillations in an infinite linear cluster of spherical nanoparticles are found analytically within the framework of the quasi-static approach and numerically within the framework of the finite element method. It is shown that the spectrum of plasmon oscillations is complex and contains previously unknown, highly localised modes in a high-frequency region of the spectrum. The results obtained can be used in designing plasmon nanowaveguides and nanolasers.