Spectral features of electromagnetic field propagation along a nanoparticle chain

Numerical calculations are performed and spectral characteristics and spatial field distributions are studied upon excitation of a chain of two and three nanoparticles by a near-field optical microscope probe. It was found that there is a set of frequencies near the absorption line of nanoparticle material, at which the electromagnetic field can most efficiently propagate along the chain. It is shown that the efficiency of the electromagnetic energy transfer due to the quadrupole interaction between particles can exceed the efficiency of the transfer caused by the dipole interaction.