Magnetic absorption of electromagnetic waves by a small metallic particle of ellipsoidal form

Abstract

The magnetic absorption of electromagnetic waves by a small metallic particle of ellipsoidal form is investigated in frequency regions both higher and lower than the characteristic frequency of the free passage of an electron between walls of the particle. The boundary conditions chosen are diffuse reflection of the electron from the inner surface of the particle. For the case when the thickness of the skin layer is large compared to the characteristic size of the particle, analytical expressions are obtained which permit determination of the dependence of the energy absorbed by a particle on its shape and orientation with respect to the direction of incidence of the radiation. The low-frequency absorption by small metallic particles is analyzed in detail for the first time. For particles in the form of oblate or prolate ellipsoids of revolution it is shown at particle sizes and what initial polarizations of the incident wave that the magnetic absorption becomes dominant over electric absorption.