Calculated magneto-optical Kerr spectra of compounds (X = V, Cr, Mn, Fe and Co)

Abstract

The magneto-optical spectra of the compounds (with X = V, Cr, Mn, Fe and Co) are calculated for their ferromagnetic phase in the crystal structure, using density-functional band-structure theory. Large polar Kerr effects are predicted for several of these compounds, with - for a reasonable spectral broadening of 0.4 eV - maximum Kerr rotations of for and , for and , respectively. The Kerr spectra of , and with (001) magnetization are found to be very similar in shape, as are also those of and . The origin of the large Kerr effect in the alloys is shown to be caused by the spin - orbit coupling strength of Pt. A magnetic moment of moderate size on the 3d atom suffices in these materials to already create an appreciable Kerr effect. The influence of the optical transition matrix elements, magnetic moments and spin - orbit coupling strength on each of the constituent atoms are furthermore analysed. The orientation dependence of the polar Kerr spectra of some of the compounds are investigated by calculating in addition the polar Kerr spectra of some compounds for the (111) magnetization axis. The Kerr spectra of the (111) magnetization are found to be practically identical to that of the (001) magnetization.

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

“…4, we show the calculated Kerr spectra for MnPt 3 together with the previous theoretical calculations performed by Oppeneer et al [24] and experimental spectra from Kato et al [10]. The maximum Kerr rotation of −1.17 • at 1.0 eV in MnPt 3 from our results compares well with the experimental value of −1.2 • at 1.2 eV.…”

“…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.…”

“…Moreover, the existence of small peaks in Kerr spectra for energies E > 4 eV is due to smaller value of 1xx (ω) in this range. [24] and experiments [10] are also shown.…”

“…Suzuki et al [23] have performed similar calculations for XPt 3 (X = V, Cr, Mn, Fe, Co) using LMTO method. Oppeneer et al [24] used the augmented spherical wave (ASW) method and fully relativistic linear muffin-tin orbital (LMTO) method to calculate the Kerr spectra of XPt 3 (X = V, Cr, Mn, Fe, Co). They obtained maximum Kerr rotation of −1.5 • for MnPt 3 , −1.0 • for CoPt 3 and −1.1 • for FePt 3 .…”

Comment on “Optical and magneto-optical properties of AuMnSn” [Appl. Phys. Lett. 88, 121909 (2006)]

“…20 So deviation between experiment and theory on the shape and magnitude of Kerr spectra ͑especially above 3 eV͒ may also be associated with the temperature-dependent SOC. It is demonstrated 21 for PtMnSb that the degree of p-d hybridization at the Pt site ͑which also changes with temperature͒ strongly influences the structure of the Kerr spectra. As this effect influences the whole energy range, its sway on the temperature-dependent Kerr spectra depends on the character of the bands in different energy ranges.…”