Penetration Of The High-frequency Electromagnetic Field Through Thin Films Of Sr-doped Lanthanum Manganites

摘要

Penetration of electromagnetic waves through thin films of La_(0.67)Sr_(0.33)MnO_3 manganite grown by pulsed laser deposition on (100) SrTiO_3 and LaAlO_3 substrates was investigated and compared to the data obtained for the bulk specimens of the same composition. Experiments were carried out in the frequency range from 50 kHz to 20 MHz. Strong frequency-dependent variations of penetration coefficient in the static magnetic field were observed both for ferromagnetic and paramagnetic temperatures. The experimental data obtained confirm preservation of a local dynamic magnetic ordering in the paramagnetic temperature range by 1.10 to 1.22 times higher than the Curie temperature. The value of upper frequency limit of the dynamic polaron correlations in the paramagnetic phase was obtained.