Magnetization Dynamics Study of Crystalline and Amorphous Polyvinylidene Fluoride Thin Films in Polyvinylidene Fluoride/CoFeNi Bilayers

Magnetization dynamics across polyvinylidene fluoride (PVDF) thin films in PVDF/CoFeNi bilayers have been systematically investigated using coplanar waveguide ferromagnetic resonance spectroscopy in broadband frequency range from 9 to 37 GHz. The influence of crystalline (mixture of nonpolar α and polar β phases) and amorphous (nonpolar) PVDF interfaces upon the magnetization dynamics is probed by calculating the Gilbert damping ( α G ) and spin‐mixing conductance ( g ↑↓ ) parameters by varying the thickness of PVDF. A higher α G and its methodical rise with the increase in thickness of crystalline PVDF thin films is noted in comparison with the nonpolar amorphous PVDF interfaces. This work suggests the feasibility of controlling the magnetization dynamics using the crystalline or polar interfaces, possibly by interfacial magnetoelectric coupling at the ferroelectric/ferromagnetic interfaces.