Magnetic Moments and Unpaired-Electron Densities in CoPt3

Abstract

The coupling of photons and magnons can be treated by the same methods developed for the coupling between photons and phonons. The coupled wave equations are derived directly from the Hamiltonian density for the quantized fields with the density-matrix formalism. The similarity between the spin Raman effect and the vibrational Raman effect is emphasized and it is shown that the spin Raman effect will usually be one or two orders of magnitude smaller than the vibrational effect in Raman liquids. The possibility of exiciting spin-wave modes by light in ferro-, ferri-, and antiferromagnetic materials is discussed. The com bined coupling of magnetic, vibrational, and light waves is also analyzed and a magnon excitation may be induced by the stimulated Brillouin effect on a magnetoelastic mode.

Magneto-optical properties of transition metal compounds XPt3 (X=V, Cr, Mn, Fe, Co) and X3Pt (X=Fe, Co)

“…In order to investigate it first, the magnetic moments have been calculated. The values for spin, orbital and total magnetic moments at X and Pt sites as well as total magnetic moment for the compound from this work and others [21,22,24,35,16] are reported in Table 2 and compared with available experimental data [3,5,8,18,[36][37][38]. The calculated magnetic moments are in good agreement with available experimental values and other theoretical calculations.…”

“…When the 3d transition metal (represented by X) is one of the elements among V through Ni, ordered XPt compounds have the CuAuI-type (or L1 0 ) structure whereas XPt 3 and X 3 Pt have the Cu 3 Au-type (or L1 2 ) structure [1,2]. Among the Cu 3 Au-type compounds with X = V to Ni, ferromagnetism is observed for MnPt 3 [3], Fe 3 Pt [4], CoPt 3 [5] and Ni 3 Pt [6] while FePt 3 exhibits antiferromagnetism with magnetic ordering vector as (1/2, 1/2,0) [7]. In the case of VPt 3 [8] and CrPt 3 [9], it is widely believed from experiments that the magnetic moments on Pt sites align in an antiparallel direction to those on the 3d transition metal sites, resulting in a ferrimagnetic ordering.…”

Inelastic neutron scattering and migration energies in FePd

“…After a period of strong research on superalloys for their magnetic [1][2][3][4][5], catalytic [6] and high temperature mechanical [7] properties, nowadays some of them arouse a new interest owing to their possible applications as shape memory alloys [8] and high density recording media because of their large magnetic anisotropy [9,10]. A good knowledge of the ordering processes and of its dynamics is thus a necessary step in any extensive research on those systems.…”

Magnetism of FePt Surface Alloys

“…Moreover, the relative size of the XMCD signal at the Pt N 7 edge suggests that the induced moment of Pt within the alloy layer is comparable to the one found in CoPt 3 . For the latter, a Pt moment of 0:26 B =atom was determined by neutron scattering [15,16].…”