Options
Study of magnetic anisotropy in Si/Ni multilayers by static and dynamic magnetization processes
Journal
Journal of Materials Science: Materials in Electronics
ISSN
09574522
Date Issued
2022-11-01
Author(s)
Singh, Dushyant
Senthil Kumar, M.
Abstract
To investigate magnetic anisotropy in Si/Ni multilayers, ferromagnetic resonance (FMR) and magnetization studies are carried out by preparing a series of samples of the form [Si(10 Å)/Ni(tNiÅ)]20, where tNi and 20 denote the Ni layer thickness and number of bilayers, respectively. The samples are prepared using a DC magnetron sputtering system by fixing the Si layer thickness at 10 Å and by varying the Ni layerthickness from 10 to 100 Å. The surface morphology study confirms that the multilayers were deposited smoothly over the substrates. The variation of the surface roughness with tNi attains a maximum for tNi = 50 Å. The structural study shows that the average crystallite size increases with as tNi increases. The magnetic anisotropy exhibited by the samples has been systematically studied through static and dynamic processes. The effective magnetization obtained from the MH loops and FMR spectra increases with increasing tNi and approaches towards the bulk value of Ni. Static and dynamic magnetization processes yeilds the values of surface anisotropy constant (Ks) and volume anisotropy constant (Kv) to be positive and negative, respectively. Through FMR studies, it is found that the rougher surfaces/interfaces lead to the multiple resonances peaks, higher asymmetry ratio, minimum value of spectroscopic splitting factor g and higher surface anisotropy.