Magnetic Characteristics of Thin Film (original) (raw)

Detection of magnetic moment in thin films with a home-made vibrating sample magnetometer

Journal of Magnetism and Magnetic Materials

This paper explores the optimization of an array of pickup coils in a home-made vibrating sample magnetometer for the detection of magnetic moment in thin films. Sensitivity function of a 4-coils Mallinson configuration was numerically studied for the determination of the physical dimensions that enhance the sensitivity of the magnetometer. By performing numerical simulations using the Biot-Savart law combined with the principle of reciprocity we were able to determine the maximum values of sensitivity and the influence of the separation of the coils on the sensitivity function. After the optimization of the pickup coils, the vibrating sample magnetometer was able to detect the magnetic moment of a 100 nm-thickness Fe 19 Ni 81 magnetic thin film along and perpendicular to the in-plane anisotropy easy axis. The implemented vibrating sample magnetometer is able to detect changes in the magnetic moment of ∼ 2 × 10 −4 emu.

Direct and inverse measurement of thin films magnetostriction

Journal of Magnetism and Magnetic Materials, 2010

Two techniques of measurements of thin film magnetostriction are compared: direct, when changes of the substrate curvature caused by the film magnetization are controlled, and inverse ("indirect"), when the modification of the magnetic anisotropy induced by the substrate deformation (usually bending) is measured. We demonstrate how both the elastic strength of the substrate and the effective magneto-mechanical coupling between the substrate deformation and magnetic anisotropy of the film depend on different conditions of bending. Equations to be used for magnetostriction value determination in typical cases are given and critical parameters for the corresponding approximations are identified.

On the vectorial calibration of a vibrating sample magnetometer for thin film measurements

Journal of Magnetism and Magnetic Materials, 1999

A calibration method for the biaxial vector Vibrating Sample Magnetometer (VSM) is proposed to reduce the so called "cross talk" error, often observed during angular measurements on magnetic thin films. The coil system of the biaxial vector VSM consists of two sets of coils, one for each of the two co-ordinate axes. The method takes into account that each coil set is sensitive to all components of the magnetisation vector and moreover that the sensitivity to the components parallel and perpendicular to the film plane can be different. A correction for demagnetisation should be used to compensate the fact that the sample used for the calibration can not be fully saturated with an applied field at angles close to the normal of the film plane. Curve-fitting on the sensitivity curves is used to reduce noise. These procedures result in a calibration which reduces the cross talk by a factor 4 to 8 depending on the coil configuration and the size and shape of the samples used.

Thin film’s magnetostriction investigated by

The novel experimental setup for measurements of magnetostriction of thin films in the temperature range starting from 4.2 K up to the room temperature, using the strain modulated ferromagnetic resonance phenomenon, is presented. The sample under investigation is fixed at the anti-node of vibrations of the longitudinal mode sapphire resonator. The resonator is excited by means of a piezoelectric transducer via the mechanical waveguide. The sapphire rod is put into a helium flow cryostat, thus allowing the measurements in the wide temperature range. The temperature gradient along the resonator length is negligible due to the very high thermal conductivity of sapphire. The setup is controlled by specially designed electronic circuit interfaced to a computer. As an illustrative example, the measurements of epitaxial Fe/GaAs(001) films were performed with in-plane magnetic field, in the temperature range between 10 K and the room temperature.

Thin Films for Magnetic Recording Tech nology : A Review

2017

Chen et al., "The Effect of Orientation, Grain Size and Polymorphism on Magnetic Properties of Sputtered Co-ReThin Film Media", IEEE Transactions on Mag netics, MAG 17, No. 6, 1981, pp. 3187-3189. Potzlberger, "Magnetron Sputtering of Permalloy for Thin-Film Heads", IEEE Transactions on Magnetics, MAG 20, No. 5 Sep. 1984, pp. 851-853. Treves, "Platinum-Cobalt Films for Digital Mag neto-Optic Recording", Journal of Applied Physics, vol. 46, No. 6, Jun. 1975, pp. 2760-2765. Allyn et al., "Thin-Film Discs: Magnetic, Electrical

Characterization Of Magnetooptical Thin Films For Sensor Use

Proceedings of SPIE, 1989

As a part of a fibre optical sensor development project we have made an evaluation of different optical waveguiding techniques to study the properties of thin magnetooptical films. Because of the application the methods are focused on the determination of the Faraday rotation, the linear birefringence and the dynamics and anisotropy of the magnetic properties of the samples. Measurements using holographic grating, prism and edge (end-fire) light coupling to different substituted YIG films are presented. The advantages of the different methods are discussed and it is shown that the launching technique may affect the properties to be measured. Film stress caused by the prism coupling method is found to influence the magnetic anisotropy.