Properties Of Ferromagnetic Thin Films Research Articles

Magneto-elastic coupling and domain structure in ferromagnetic films near the phase transition

The magneto-elastic properties of thin ferromagnetic films near to the phase transition from the state of homogeneous magnetisation to the state of domain structure in the temperature region T<<Tc are considered. The phase transition is caused either by a change of the film thickness or external magnetic field. Formulae describing magnetic, magneto-elastic and elastic susceptibility tensors are derived. The dispersion relation describing the soft mode of coupled magnetic-elastic excitations is obtained.

Relations between some galvanomagnetic and magnetic properties of thin ferromagnetic films

physica status solidi (a)Volume 106, Issue 1 p. K75-K78 Short Note Relations between some galvanomagnetic and magnetic properties of thin ferromagnetic films L. Vatskichev, L. Vatskichev Faculty of Physics, Sofia University Search for more papers by this authorM. Vatskicheva, M. Vatskicheva Faculty of Physics, Sofia University Search for more papers by this author L. Vatskichev, L. Vatskichev Faculty of Physics, Sofia University Search for more papers by this authorM. Vatskicheva, M. Vatskicheva Faculty of Physics, Sofia University Search for more papers by this author First published: 16 March 1988 https://doi.org/10.1002/pssa.2211060152 Blv. Anton Ivanov 5, BG-1126 Sofia, Bulgaria. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume106, Issue116 March 1988Pages K75-K78 RelatedInformation

Magnetic properties of thin ferromagnetic films in relation to their structure

The influence of film structure on magnetic properties is primarily due to the creation of spatially fluctuating local anisotropies which make the magnetization direction inhomogeneous. The deviation from homogeneous magnetization of domains, the so-called ripple, influences a great number of static, quasistatic and dynamic effects via the intrinsic demagnetizing field. The ripple theory is expressed in terms of only one phenomenological constant, the structure constant S, which covers completely the influence of the film structure on the deviations of real thin film behaviour from that of ideal single domains.

Magnetic Properties of Ferromagnetic Thin Films Prepared by Ion Plating

Thin films of Fe, Co and their alloys were prepared by ion plating. Metals were evaporated in the argon gas atmosphere of about 0.01 Torr, by applying a dc electric field of 2 kV/15 cm between the substrate and the evaporation source. Since evaporated metal atoms, which were given large kinetic energies by the gas plasma, impinged on the surface of the substrate, a strong adhesion between the ferromagnetic thin films and the substrate could be obtained. Due to the granular structure of the thin film, a higher coercive force and the squareness ratio could be obtained: i.e. by changing the Ar gas pressure, the coercive force and the squareness ratio could be controlled up to 500 Oe and 0.6, respectively, and also they were controlled by choosing the constituents of the mother alloys.

Methods for studying the pulsed properties of thin ferromagnetic films

Methods for studying the pulsed properties of thin ferromagnetic films

Electro deposition: A convenient method for monitoring the magnetic properties of ferromagnetic thin films

Electro deposition: A convenient method for monitoring the magnetic properties of ferromagnetic thin films

Sensitive Automatic Torque Balance for Thin Magnetic Films

An automatic torque balance has been constructed for use in studying the magnetic properties of thin ferro-magnetic films. The automatic servo force balancing technique using a photoelectric pickoff has been applied to a fused-silica torsion fiber suspension. A sample up to 600 mg in weight can be handled. The data are automatically recorded by an X-Y plotter. Sensitivity of 10−6 dyn-cm and a response time of a fraction of a second have been obtained, providing a significant improvement over similar instruments previously used. An appropriate set of coils provides the magnetic field H. Since the torque on a sample is given by M×H=L, measurement of torque affords a means of studying the behavior of the magnetization M. Provision is made for observing torque either parallel or perpendicular to the film surface. The sensitivity available will permit the study of 1-cm-diam films as thin as one-half an atomic layer under ideal conditions. Examples are given of the measurement of the saturation magnetization, remanent magnetization, anisotropy constant, and coercive field on a 35-Å film, showing the quality of the data. The anisotropy field and the squareness are calculated from the above quantities. Observations of rotational hysteresis loss are also discussed.

Magnetic anisotropy in thin ferromagnetic films

The magnetic properties of thin ferromagnetic films are studied taking into account the magnetic anisotropy term in the Hamiltonian. In the second approximation equations are obtained for the magnetization of the monatomic layers parallel to the surface of the thin film. From these equations one obtains the Curie temperature, which depends on the thickness of the thin film and the ratio a between the anisotropy constant and the exchange energy between two neighbours. A value can be chosen forα such that the thin film becomes ferromagnetic only for a thickness greater than a definite value and in this manner the theoretical results can be fitted to the experimental data. The situation in cobalt thin films is dealt with in particular.

Thin Ferromagnetic Films

This article gives an account of the work at the Royal Radar Establishment (RRE), Malvern, England, on the preparation and properties of thin ferromagnetic films. The work provides the prospect of a computer store in which a million bits would occupy less than an 18-inch cube, and which would possess a switching time faster than 20 mµsec. The store would be cheap and easily constructed.