H. Ikekame

Fundamental studies and application of short-wavelength magneto-optical effect in Pt-based multilayers

Abstract Recent trends in the research and development to realize higher recording densities in magneto-optical (MO) disk systems are briefly reviewed, with particular emphasis on the importance of developing the short-wavelength media. A brief review of Pt-based multilayers for MO recording is given, and fundamental MO properties in Pt/Fe, Pt-Co and Pt/NiCo multilayers are discussed in detail based on our studies of MO spectra for the wide-wavelength region.

Magnetic polarization of interfacial Pt in FePt/Pt multilayers witnessed by magneto-optical spectra

Magneto-optical spectra in FePt(x A)/Pt(50 A) multilayers prepared by the ion-beam sputtering technique were measured between 1 and 6 eV. Simulation by the virtual optical constant method, assuming the existence of a magnetic Pt layer at the interface, provided a fairly good explanation of the x-dependence of the magneto-optical spectra. The magnetic coupling between FePt and Pt was found to be antiparallel for x ≥ 50 and parallel for x < 50.

Effects of atomic-hydrogen assistance on hot-wall epitaxy growth of MnSbGaAs heterostructures

Prominent improvement of surface flatness was observed in MnSb films prepared by atomic-hydrogen assisted hot wall epitaxy technique on GaAs substrate. The effect is discussed in terms of surfactant effect of atomic hydrogen.

Magneto-optical spectra in Co-based multilayers

Abstract Magneto-optical spectra of Pd/Co multilayers were measured between 1.2 and 5.9 eV, from which the off-diagonal elements of the conductivity tensor were deduced and were compared with those of Pt/Co multilayers.

Magneto-optical spectra in MnSb and MnAs films prepared by atomic-hydrogen assisted hot wall epitaxy on GaAs

Thin films of NiAs-type MnSb and MnAs were epitaxially grown on GaAs (1 0 0) and (1 1 1) substrates by an atomic-hydrogen assisted hot-wall technique. Polar magneto-optical spectra were measured between 1.2 and 6 eV. Crystal-orientation dependence of the spectra were clearly observed.

Magnetooptical Spectra in Pt-Ni Alloys and Multilayers

Pt-Fe, Pt-Co and Pt-NiCo alloys and multilayer films were prepared on a SiO2 substrate by the dc magnetron sputtering technique. The reflectivity spectra and magnetooptical Kerr spectra of these specimens were measured, and the diagonal and off-diagonal elements of the conductivity tensor were deduced. The results of this work are as follows: (1) The peak energy position of the magnetooptical Kerr rotation spectra showed a systematic shift to lower energies as the transition metal was changed from Fe to Ni, both in multilayer and alloy samples. (2) Simulation using the above-determined conductivity tensor for alloys revealed that alloy layers exist at the interfaces between Pt and the transition metal in all the Pt-based multilayer films investigated. (3) Obvious effects of plasma enhancement were confirmed in the short-wavelength magnetooptical Kerr spectra of the Pt-based alloys.