Unexpected resonant response in [Fe(001)/Cr(001)]_(10) /MgO(001) multilayers in magnetic field

TL;DR

This study reports an unexpected resonant response in Fe/Cr multilayers under combined ac current and magnetic field, linked to multilayer magnetization and interface effects, revealing new insights into thin film vibrations.

Contribution

It uncovers a novel resonant phenomenon in Fe/Cr multilayers induced by simultaneous ac current and magnetic field, highlighting the role of interface transition zones.

Findings

Resonances depend on multilayer magnetization.

Interface quality affects resonance behavior.

Resonances occur only with combined ac current and magnetic field.

Abstract

We observed unexpected resonant response in [Fe/Cr]_(10) multilayers epitaxially grown on MgO(100) substrates which exists only when both ac current and dc magnetic field are simultaneously applied. The magnitude of the resonances is determined by the multilayer magnetization proving their intrinsic character. The reduction of interface epitaxy leads to non-linear dependence of the magnitude of resonances on the alternating current density. We speculate that the existence of the interface transition zone could facilitate the subatomic vibrations in thin metallic films and multilayers grown on bulk insulating substrates.