Scattering Theory of Small-Particle Absorption: Cyclotron and Magnetoplasma Resonance

Abstract

The excitation of a small ellipsoidal sample in an electromagnetic cavity is treated quantitatively as a two-wave Rayleigh-scattering problem. Application to the special case of a solid-state magnetoplasma shows that magnetoplasma resonance occurs when ${\ensuremath{\kappa}}^{\ensuremath{'}}=\ensuremath{-}(\frac{1}{L\ensuremath{-}1})$, with strength proportional to $\frac{1}{{\ensuremath{\kappa}}^{\ensuremath{'}\ensuremath{'}}}$, and approximate half-width ${\ensuremath{\kappa}}^{\ensuremath{'}\ensuremath{'}}$, where $\ensuremath{\kappa}={\ensuremath{\kappa}}^{\ensuremath{'}}+i{\ensuremath{\kappa}}^{\ensuremath{'}\ensuremath{'}}$ is the net bulk dielectric constant of the material comprising the ellipsoid, and $L$ is the mks depolarization factor. New methods of deducing transport parameters from magnetoplasma resonance are outlined.