Retardation Effects in Azbel'-Kaner Cyclotron Resonance

Corrections to the Azbel'-Kaner theory of the magnetic-field-dependent surface impedance of metals have been calculated. The results illustrate the effects of the finite transit time of the electrons in their passage through the skin layer. The cyclotron-resonance line shapes are modified from the Azbel'-Kanel results for both the high-(ωcτ) and low-(ωcτ) limits. The bearing of these results on experimental determinations of carrier effective masses and relaxation times are discussed. Finally, the background signals from the nonresonant electrons are calculated for an arbitrary cutoff angle for specular reflection of the electrons at the surface.