Temperature Dependence Of Spontaneous Magnetization Research Articles

Temperature Dependence of Spontaneous Magnetization of the FeCr2−xInxS4 (0 ≦ x ≦ 1) System

physica status solidi (a)Volume 73, Issue 2 p. K209-K212 Short Note Temperature Dependence of Spontaneous Magnetization of the FeCr2−xInxS4 (0 ≦ x ≦ 1) System R. Z. Sadikhov, R. Z. Sadikhov Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorI. G. Kerimov, I. G. Kerimov Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorL. M. Valiev, L. M. Valiev Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorA. D. Namazov, A. D. Namazov Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this author R. Z. Sadikhov, R. Z. Sadikhov Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorI. G. Kerimov, I. G. Kerimov Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorL. M. Valiev, L. M. Valiev Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this authorA. D. Namazov, A. D. Namazov Institute of Physics, Academy of Sciences of the Azerbaidzhan SSR, Baku Search for more papers by this author First published: 16 October 1982 https://doi.org/10.1002/pssa.2210730257Citations: 3 Prospekt Narimanova 33, Baku 73, USSR. 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 Citing Literature Volume73, Issue216 October 1982Pages K209-K212 RelatedInformation

Electron-phonon interaction and itinerant-electron ferromagnetism

Starting from a consideration of how the phonon frequency would change with the spin splitting of the conduction-electron energy bands in an itinerant-electron ferromagnet, we find that in the paramagnetic region the effect of the electron-phonon interaction makes the temperature dependence of the spin susceptibility Curie-Weiss-type, with the Curie temperature ${T}_{C}$ much lower than in the Stoner theory. Further, for $T<{T}_{C}$ we find that the phonon effect on magnetization can be large enough to account for the anomalous temperature dependence of spontaneous magnetization often observed in itinerant-electron ferromagnets, especially in Invar alloys. To confirm such a conclusion, with the same model and approximation we discuss also the very closely related problem of the magnetic field effect on the sound velocity in an itinerant-electron ferromagnet, and our theory is found to explain satisfactorily the varied observed results for both $T>{T}_{C}$ and $T<{T}_{C}$.

Low spin states in invar alloys—The invar problems

The low spin model proposed by Weiss (1963) to account for Invar anomalies is reviewed, together with its various modifications. Then anomalous thermal expansion and a steep temperature dependence of spontaneous magnetization were reproduced by computer simulation for 35 at% Ni-Fe Invar and Fe 3Pt with various degrees of order, by assuming that the energy of low spin state of Fe atoms and the exchange coupling between high spins both depend upon the number of nearest neighbor Fe atoms. The results are discussed in relation to the various experiments including Mössbauer spectroscopy. The relation to the band picture will be briefly discussed.

Computer Simulation of Temperature and Field Dependences of Sublattice Magnetizations and Spin-Flip Transition in Gallium-Substituted Yttrium Iron Garnet

On the basis of the molecular field model, sublattice magnetizations in gallium-substituted yttrium iron garnet Y 3 Ga x Fe 5- x O 12 are calculated over a wide range of x , temperature and applied magnetic field with a computer program. Comparing the calculated temperature dependence of spontaneous magnetization, the critical fields of the spin-flip transition at high magnetic fields and the ferrimagnetic Curie temperature, with experimental data, the super-exchange coefficients in YIG and Y 3 Ga x Fe 5- x O 12 were evaluated.

The temperature dependence of some thermodynamical quantities of ferromagnetic alloys in the region of magnetic phase transition

This paper deals with the behaviour of ferromagnetic alloys in the region of magnetic phase transition. The temperature dependences of spontaneous magnetization, magnetic susceptibility and specific heat are discused. The theoretical results are compared with experimental data.

NMR study of the magnetisation of the nearly two-dimensional heisenberg ferromagnets (CnH2n+1NH3)2CuCl4with n=1,2,3,4,8,10

The magnetisation of the nearly two-dimensional weakly anisotropic ferromagnets (CnH2dn+1NH3)2CuCl4 has been studied by means of Cu and Cl nuclear magnetic resonance. The hyperfine interaction of Cu and Cl nuclei and the Cu2+ spin direction were determined. The field dependence of the magnetisation has been measured in the range 0 to 10 kOe. This allowed the intralayer exchange integral J to be determined using simple spin-wave theory taking into account experimental magnetic anisotropy and interlayer exchange. The temperature dependence of spontaneous magnetisation measured in the range 1.4 to 4.2K is well described by the theory using this J value.

Temperature Dependence of Spontaneous Magnetization and Hypeŕfine Fields in GdAl2 and GdZn

The magnetization was measured at 4.2 to 300 deg K. Zero-field resonanccs of /sup 155/Gd, /sup 157/Gd, /sup 27/Al, and /sup 67/Zn were determin ed using spin-echo techniques, and hyperfine field coupling constants were also determined. Hyperfine fields at the magnetic and nonmagnetic ion sites were determined. The coupling constant for the core polarization varies 1.5% per 8O deg K for GdAl/sub 2/ and 1.0% per 170 deg K for GdZn. (DLC)

Temperature Dependence of Spontaneous Magnetization in Superparamagnetic Nickel

The possibility of an anomalous temperature dependence of the spontaneous magnetization of superparamagnetic particles has been the subject of several investigations which are in contradiction. We have investigated nickel particles in the 30–100 A diameter range. These were prepared on silica gel supports in the manner familiar in contact catalysis. The spontaneous magnetization in these small particles is slightly but measurably lower than that of massive nickel. The calculated Curie temperature of a sample with average particle diameter of 30 A was about 565°K. It proved impossible to confirm the large variations of Curie temperature, strongly dependent on particle size reported recently for similar preparations.