Упругие резонансы в структуре: тонкая магнитная пленка – толстая упругая подложка

Abstract

The task about excitation of connected magnetic and elastic vibrations in flat-parallel-structure consisted of thin magnetic film applied on thick nonmagnetic substrate is considered. For the solution of this task the model of propagation periodic boundary regime is proposed. This solution allowed to build the amplitude-frequency characteristics of magnetic and elastic vibrations. In this case the characteristic of magnetic vibrations has the view as wide bell-like maximum on which is put by equidistance net of narrow elastic resonances which divided one to another on the frequency elastic resonance along the substrate thickness. It is executed the model presentation of superposition elastic resonances on magnetic using the system of two connected oscillators which frequencies differs in some orders. It is supposed the mechanism of superposition elastic resonances on magnetic characteristic which consist of coincidence wave phase after two-path wave passage through the substrate thickness and phase of initial excitation. It is investigated the influence of elastic wave dissipation on the structure of amplitude-frequency characteristics of magnetization and elastic displacement. It is found the critical value of elastic dissipation parameter. It is shown that below of this value the elastic vibrations have resonance character and higher become non-periodical. It is found the inversion value of dissipation parameter which determined the transition from symmetrical distribution of elastic resonances on magnetic characteristic to anti-symmetrical. It is shown that the inversion value of dissipation parameter more (on two-three orders) smaller that critical value. It is found the phenomenon of second elastic resonance which is consist of exceeding frequency maximum rounding of elastic resonance net over the frequency of maximum magnetization characteristic. It is found the connected with dissipation second resonance splitting which take place near the neighbouring of inversion value dissipation parameter.