Atomic Force Microscopy Measurements of Magnetostriction of Soft-Magnetic Films

Abstract

A method for direct measuring the magnetostriction of ferromagnetic films (deposited on nonmagnetic substrates) in using an atomic force microscope was suggested. In measuring the magnetostriction for films 10 [mm] in length and 0,2 [μm] in thickness, which were deposited on substrates 200 [μm] thick, the minimum measured magnetostriction magnitude is ~10-7. The procedure was tested for Ni and Fe films. The magnetostriction magnitudes measured for the films are comparable with those obtained by other magnetostriction-measuring methods. The effect of alloying with zirconium and nitrogen on the magnetostriction of nanocrystalline Fe films was studied.

Direct method for magnetostriction coefficient measurement based on atomic force microscope, illustrated by the example of Tb–Co film

“…But, in the last decades it was stated that this quadratic correlation only applies for some special conditions, as the reversal of the magnetization process by 90° domain walls or by collective rotation of the magnetization [8,10]. In these two cases, equation 1 represents the dependence of the magnetostriction coefficient as a function on the magnetization of the sample, ( ) (1) where  S and M S are the magnetostriction coefficient and the magnetization for the magnetically saturated state, respectively.…”

“…The sample was adhered to the sample holder through a double-face adhesive tape. The coefficient of magnetostriction  can be obtained from deflection D of the sample by the following equation [8],…”

“…In ref. [7], a technique for magnetostriction measurement on magnetic wires using AFM was developed, and more recently, Harin et al [8] have proposed using AFM technique for the measurement of the magnetostriction coefficient in thin magnetic films on nonmagnetic substrates. However, in [8], the variation in the dimensions of the film studied with the application of the magnetic field, and the setup used for the measurements were not clearly presented.…”

Measurement of thin film magnetostriction using field-dependent atomic force microscopy

“…Early studies have employed conventional AFM imaging for magnetostriction measurements on metallic wires [30,31]. More recently, it has successfully been demonstrated for thin film magnetostriction by measuring the tip deflection of micromachined macro-cantilevers (a few millimetres to centimetres in size), coated with Fe, Ni, Co and Tb based magnetostrictive films [32,33]. In a related approach for dynamic force microscopy in liquid environments, the AFM probes (with micro-cantilevers a few µm in size) have been directly coated with 50 nm films of magnetostrictive Fe-B-N, to drive their mechanical oscillation [34].…”

Modelagem e fabricação de modulador em óptica integrada baseado em filme magnetostrictivo para aplicação como magnetômetro.

“…O coeficiente de magnetostricção, m, pode ser obtido através da equação (HARIN, et al,2012), a seguir.…”