C 73 Complex dynamics of magnetic-flux oscillations in bulk lead-doped lanthanum manganite / A. P. Nosov, A. B. Rinkevich, V. V. Ustinov, V. G. Vasil'ev // The Physics of Metals and Metallography. - 2009. - Vol. 107, № 1. - P34-44 : il. - Bibliogr. : p. 43-44 (27 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ДОПИРОВАНИЕ -- СВИНЕЦ -- МАНГАНИТЫ -- МАГНИТНЫЕ КОЛЕБАНИЯ Аннотация: Magnetic-flux oscillations in a core made from lead-doped lanthanum manganite have been investigated. The core was located in crossed dc and radio-frequency ac magnetic fields. At a sufficiently large ampltude of the rf field, magnetic-flux jumps were observed and regions of ultrasharp oscillations of the magnetic flux appeared, which correspond to a bifurcation of a soft generation of a limit cycle. Flattened segments appeared in the oscillograms. The phenomena observed are qualitatively explained based on an analysis of processes of the dynamic magnetization reversal of the core along a minor hysteresis loop. The nonlinear phenomena, which indicate a complex dynamics of the magnetic-flux oscillations, exist in a moderately conducting feromagnetic manganite only in a certain range of frequencies of the ac field, where the depth of a skin layer is comparable with the thickness of the core Полный текст |