IV-VI diluted magnetic semiconductor Ge0.92Mn0.08Te epilayers are grown on BaF2 substrates by molecular beam epitaxy. The ferromagnetic behaviors, such as the spontaneous magnetization, the coercive field, and the Curie temperature TC, are altered by the hole concentration p. In the Ge0.92Mn0.08Te layer with high p, strong magnetic anisotropy and the temperature dependence of the magnetization expected for homogeneous ferromagnets are observed, implying that long-range ordering is induced by the holes. The maximum TC reaches 190 K for 1.57×1021 cm−3.

We succeeded in constructing a vacuum-ultraviolet circular dichroism (VUVCD) spectrophotometer with a small-scale synchrotron radiation source (0.7 GeV) at Hiroshima Synchrotron Radiation Center (HiSOR). This VUVCD system revealed for the first time the CD spectra of amino acids in aqueous media in the 310–140 nm region under high vacuum. These data, which cannot be observed by any types of existing CD spectrophotometers, now open a new field in the structural analysis of biomaterials on a basis of the higher energy transition of chromophores.

Growth of the IV-VI diluted magnetic semiconductor Ge1−xMnxTe by molecular beam epitaxy is reported. The epitaxial growth of Ge1−xMnxTe (x=0.13) on BaF2 (111) with a GeTe buffer layer is confirmed by x-ray diffraction and reflection high-energy electron diffraction. The ferromagnetic order is clearly established by the magnetization and magnetotransport measurements. The Curie temperature of 100K is obtained for the hole concentration of 7.86×1020cm−3. The existence of the strong p-d exchange which gives rise to the ferromagnetic order is revealed by the hard x-ray photoemission measurements.

Mn L 2,3 x-ray absorption and magnetic circular dichroism study has been performed on IV-VI ferromagnetic semiconductor Ge 1−x Mn x Te with different Mn compositions x = 0.12, 0.32, 0.51, and 1. The absorption and dichroism line shapes are found to be almost independent of the Mn composition, suggesting that the local chemical environment of Mn atoms is the same for Ge 1−x Mn x Te with the wide range of x. On the basis of the configuration interaction analysis for a MnTe 6 cluster, the electronic structure parameters such as the p-d hybridization and the p-d exchange constant have been estimated.

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