We study the Heisenberg antiferromagnet on a triangular lattice with √3 × √3-type distortion by numerical-diagonalization method. We obtain the zero-temperature magnetization process and the temperature dependence of the magnetic susceptibility. Our results suggest that, between the nondistorted triangular-lattice and dice-lattice systems, a nontrivial intermediate phase appears, where a spontaneous magnetization occurs but its magnitude is smaller than one-third of the saturated magnetization. In the small-distortion region toward the spontaneously magnetized phase, the magnetic susceptibility shows a two-step behavior of its peak structure.

Ionic conductivity was measured on lanthan gallrate based ceramics under quasi-millimetre-wave (MMW) irradiation heating and conventional heating. Conductivity enhancement was evaluated for these ceramics and compared with our previous report on stabilised zirconia and doped ceria ceramics. The ionic conduction for the various amount of magnesium substituted lanthan gallrate ceramics was enhanced under MMW irradiation heating. These results are discussed in terms of the activation energies for vacancy–ion dissociation and ion transfer.

This study investigated the conductivity of lithium ions in new pyrochlore materials. A two-step synthesis method, comprising a simple solid-state reaction followed by a high-pressure solid-state reaction was used to synthesize single-phase undoped LiSrB₂O₆F (where B = Nb⁵⁺ or Ta⁵⁺). The samples were doped with the lower valent cation, Zr⁴⁺, which replaced Nb⁵⁺ or Ta⁵⁺ at B-sites in LiSrB₂O₆F and similarly, A-site point defects were introduced by reducing the amount of Sr in the sample. The crystal structure was determined by Rietveld analysis of the X-ray synchrotron diffraction data. Ionic conductivities of the samples were evaluated using electrochemical impedance spectroscopy. Sr²⁺ deficient samples showed better conductivity (8.21 × 10⁻⁶ S cm⁻¹ for Nb-containing samples and 6.38 × 10⁻⁶ S cm⁻¹ for Ta-containing samples at 300°C) than that of Zr⁴⁺-doped samples (5.58 × 10⁻⁶ S cm⁻¹ for Nb-containing samples and 3.58 × 10⁻⁶ S cm⁻¹ for Ta-containing samples at 300°C).

It was found in the early 1990s that bulk metallic glasses (BMGs) are formed by use of high stability of supercooled liquid to crystallization which can be achieved only for multicomponent alloys with the three-component rule. Since then, much effort has been devoted to clarify the formation ability, atomic configuration, microstructure, thermal stability and various fundamental properties of BMGs. More recently, further high-order multicomponent nonequilibrium bulk alloys, which have been called as high entropy (HE) type alloys, have attracted special interest and the HE alloys have also been extended to crystalline bulk supersaturated solid solution alloys as well as BMGs. This paper aims to present the structure, thermal stability and mechanical properties of HE BMGs, Pseudo-HE BMGs and HE amorphous alloys, in addition to ordinary BMGs, and to investigate the features and prospects of their new high-order multicomponent glassy and amorphous alloys.

The microstructure and magnetic properties of rapidly solidified in Cu_43.2Ag_32.0La_4.8Fe₂₀ (at.%) alloy, which was designed as the combination of Cu-Ag-based Cu₅₄Ag₄₀La₆ alloy with high glass forming ability and Fe, was investigated. The composite of an amorphous phase and crystalline phases was obtained in melt-spun ribbons. The spherical Fe globules, which was surrounded by Cu-rich crystalline phases, were embedded in Cu-Ag-La based amorphous matrix. The particular structure in melt-spun ribbons can be explained by the liquid phase separation and the crystallization of the separated Fe-rich liquid globules during the cooling of the thermal melt. The melt-spun ribbon shows the typical ferromagnetic magnetic properties due to the ten nano-meter ordered bcc-Fe based globules.

X-ray phase contrast imaging with an X-ray Talbot interferometer has attracted attention because it exhibits high sensitivity for materials consisting of light elements with weak X-ray absorption. In order to improve the sensitivity of X-ray Talbot interferometer, the development of amplitude grating (G2) with a high aspect ratio is necessary. Conventionally, such gratings are fabricated by electroplating of Au. However, this technique suffers from its high cost and is time consuming to obtain large-area uniform pattern. Recently, Yashiro et al. have developed an innovative method to fabricate high aspect ratio gratings in low cost. They applied imprinting method using viscous flow of Pd_42.5Ni_7.5Cu₃₀P₂₀ metallic glass and successfully fabricated grating G2 with aspect ratio of 2.5. Furthermore, they also demonstrated that the grating can be used for X-ray phase contrast imaging with an X-ray Talbot interferometer. In the present study, we intend to optimize the imprinting conditions of Pd-based metallic glass to achieve higher aspect ratio, and metallic glass with maximum filling depth was estimated by resistance heating.