Low-frequency dispersion of the effective transverse conductivity in inhomogeneous media in strong magnetic field

On crystalline silicon specimens with a nonuniform carrier concentration distribution produced by an optical method, a dispersion of the effective transverse conductivity sigma(perpendicular to)(eff)(omega) is observed near the frequency omega approximate to omega(c) = tau(perpendicular to)(-1) equivalent to epsilon/4 pi sigma(perpendicular to)(eff). At omega < omega(c), an anomalous transverse effective conductivity is observed: sigma(perpendicular to)(eff)(omega) is greater than the transverse conductivity of a homogeneous specimen sigma(perpendicular to)(h)(omega) (in the frequency range studied in the experiment, sigma(perpendicular to)(h)(omega) = const). Near omega approximate to omega(c), the conductivity sigma(perpendicular to)(eff) decreases, and, at omega > omega(c), it coincides with sigma(perpendicular to)(h). (C) 2000 MAIK "Nauka / Interperiodica".