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A material highway for building up crystal lattices and heterojunctions from molecular layers has been developed based on a concept of combinatorial lattice integration. The atomic-scale precision of automated multilane paving of multilayered thin films is in situ monitored by concurrent reflection high-energy electron diffraction. The designed nanolayered structures are rapidly verified by a concurrent x-ray diffractometer which has been developed for the purpose of this technology. This scheme corresponds to the concurrent two-dimensional Merrifield synthesis to form a variety of sequence-controlled layer structures in parallel and should be widely applicable for systematic fabrication and property screening of nanostructured materials and devices.

We observed ultra-short laser pulse-induced transient optical anisotropy in a LaMnO3 thin film. The anisotropy was induced by laser pulse irradiation with a fluence of less than 0.1 mJ/cm2 at room temperature. The transmittance and reflectance showed strong dependence on the polarization states of the pulses. For parallel and perpendicular polarization states, there exists a difference of approximately 0.2% for transmittance and 0.05% for reflectance at 0.3 ps after the irradiation with a pump pulse, respectively. The theoretical values for optical transmittance and reflectance with an assumption of an orbital ordering of 3d eg electrons in Mn3+ ions showed good agreement with the experimental results, demonstrating that the transient optical anisotropy in LaMnO3 thin film is due to the photo-induced symmetry-breaking of orbital ordering in excited states.

We have investigated change in the electronic structures of atomically controlled ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}\mathrm{Mn}{\mathrm{O}}_{3}$ (LSMO) thin films as a function of hole-doping levels $(x)$ in terms of in vacuo photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS) measurements. The in vacuo PES measurements on a well-ordered surface of high-quality epitaxial LSMO thin films enable us to reveal their intrinsic electronic structures, especially the structure near the Fermi level $({E}_{F})$. We found that overall the features of the valence band as well as the core levels monotonically shifted toward lower binding energy as $x$ was increased, indicating the systematic chemical-potential shift of LSMO thin films with hole doping. The peak nearest to ${E}_{F}$ due to the ${e}_{g}$ orbital is also found to move toward ${E}_{F}$, while the peak intensity decreases with increasing $x$. The loss of spectral weight with $x$ in the occupied density of states was compensated by the simultaneous increment of the shoulder structure in O $1s$ XAS spectra, suggesting the existence of a pseudogap, that is, a lowering in spectral weight at ${E}_{F}$, for all metallic compositions. These results indicate that the simple rigid-band model does not describe the electronic structure near ${E}_{F}$ of LSMO, and that the spectral weight transfer from below to above ${E}_{F}$ across the gap dominates the spectral changes with $x$ in LSMO thin films.

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005

The menopause has significant implications in women's life from several aspects. In order to give some suggestion to women's way of life, we studied history obtaining from the records at cancer examination in two institutions, and investigated about the factors influencing natural menopausal age. The results were as follows: 1) The age distribution of menopause was from about 30 to 59, with mean value of 50.0±3.5 (SD). 2) In 1906 to 1932 of birthyears, when the number of pregnancy and delivery decreased gradually, menopausal age unchanged. 3) In 5 geographic areas, where significant differences were found in menarcheal age, marital age, numbers of pregnancy and delivery, menopausal age showed contant value. 4) There exists no significant relationship between menarcheal age and menopausal age. 5) In the group of early marriage before 22 yr old, significant positive correlation was noted between marital age and menopausal age. 6) From the viewpoint of physique, significant positive correlation was found between BMI (adiposity) and menopausal age, excluding women with BMI beyond 25 (upper limit of normal range). 7) Menopausal age tended to show lower in never-pregnant or never-delivered group in physicalworker, in smoker, in non-favorite group of meat, beans and sweets, in favorite group of salt taste, and in gorup used artificial milk for infant rearing, than the opposite group, respectively. As above, menopausal age proved to relate closely to more individual factors rather than social or environmental factors.