Magnetic-field-assisted giant penetration of a radio-frequency electromagnetic field in lanthanum manganites

The penetration of an electromagnetic field in the frequency range of 20 kHz to 30 MHz through the plates of bulk polyerystalline sintered La/sub 0.60/Pb/sub 0.4/MnO/sub 3/ and La/sub 0.70/Y/sub 0.07/Ba/sub 0.23/MnO/sub 3/ manganites was studied. A giant increase, up to 10 times, of the transmission coefficient, on application of the magnetic field, was found. Skin depth variations were caused mainly by variation of the dynamical reversible magnetic permeability. The contribution of the magnetic permeability dispersion to the frequency dependence of skin depth was clarified.