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Hydrolysis of the phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2) at the cell membrane induces the release of inositol 1,4,5-trisphosphate (IP3) into the cytoplasm and diffusion of diacylglycerol (DAG) through the membrane, respectively. Release of IP3 subsequently increases Ca2+ levels in the cytoplasm, which results in activation of protein kinase C α (PKCα) by Ca2+ and DAG, and finally the translocation of PKCα from the cytoplasm to the membrane. In this study, we developed a metabolic reaction–diffusion framework to simulate PKCα translocation via PIP2 hydrolysis in an endothelial cell. A three-dimensional cell model, divided into membrane and cytoplasm domains, was reconstructed from confocal microscopy images. The associated metabolic reactions were divided into their corresponding domain; PIP2 hydrolysis at the membrane domain resulted in DAG diffusion at the membrane domain and IP3 release into the cytoplasm domain. In the cytoplasm domain, Ca2+ was released from the endoplasmic reticulum, and IP3, Ca2+, and PKCα diffused through the cytoplasm. PKCα bound Ca2+ at, and diffused through, the cytoplasm, and was finally activated by binding with DAG at the membrane. Using our model, we analyzed IP3 and DAG dynamics, Ca2+ waves, and PKCα translocation in response to a microscopic stimulus. We found a qualitative agreement between our simulation results and our experimental results obtained by live-cell imaging. Interestingly, our results suggest that PKCα translocation is dominated by DAG dynamics. This three-dimensional reaction–diffusion mathematical framework could be used to investigate the link between PKCα activation in a cell and cell function.

We studied the dependence of the electronic specific heat Cel/T on the magnetic field up to H = 8 T in a dilute quadrupolar compound Pr0.05La0.95Pb3 with a non-Kramers Γ3 doublet in the crystal-ele...

My dissertation “Restoring Honor: Japanese Pacific War Disabled War Veterans from 1945 to 1963” examines the lives of Japanese disabled war veterans and the activism of the Japanese Disabled Veterans Association (JDVA: Nippon Shōigunjin kai) in the early postwar period, beginning immediately following the Allied Occupation in the summer of 1945 and ending in 1963, when the National Diet passed the “Act on Special Aid to the Wounded and Sick Retired Soldiers” (Senshōbyōsha Tokubetsu Engo-hō). Established in 1952, the JDVA would play a leading role in securing welfare for Japanese disabled war veterans. In Japan as everywhere in the modern era, war exacted a huge price quantified in the death and maiming of soldiers. Victories in the First Sino-Japanese War (1894-1895) and the Russo-Japanese War (1904-1905) came at the cost of significant numbers of Japanese casualties. After the Japan’s victory in the Russo-Japanese War, Japan’s prestige rose remarkably as it came to be recognized as a major power. Simultaneously, the government had to address the pressing issue of war injured soldiers. The government responded by establishing a series of welfare provisions for disabled war veterans. By providing generous support for disabled soldiers, the government sought to bolster the morale of its citizens. The basic policy for disabled war veterans remained in place until the conclusion of the Pacific War. The Allied powers led by the U.S. initially aimed to extirpate wartime militarism in all its forms and as a consequence, virtually abolished preferential treatment for disabled war veterans. Experiencing the loss of the privilege that they had enjoyed and drastic changes of social status from the prewar to the postwar period, the disabled veterans engaged in organized efforts in quest of life security and recovery of honor after the end of the Allied occupation. This dissertation explores the reintegration of Japanese disabled veterans into civilian life in the shadow of war. In examining Japanese disabled war veterans, it is

The tetragonal ternary compound TbIr 2 Si 2 shows polymorphism; the ThCr 2 Si 2 -type structure as a low temperature phase (I-phase) and the CaBe 2 Ge 2 -type one as a high temperature phase (P-phase) exist. In order to compare with magnetism of the morphs, magnetic measurements were performed on the I- and P-phase single crystals. The magnetic behavior changes drastically depending on the structure. The TbIr 2 Si 2 (I) shows an antiferromagnetic ordering below T N =80 K, a strong uniaxial magnetic anisotropy with the easy [001] direction, and isotropic magnetic behavior in the basal plane. The [001] magnetization shows a clear two-step metamagnetic transition: an Ising-like behavior at low temperatures. On the other hand, the TbIr 2 Si 2 (P) has the comparatively low ordering temperature of T N1 =11.5 K and an additional transition temperature of T N2 =5 K, and exhibits an easy-plane magnetic anisotropy with the easy [100] direction. A strong magnetic anisotropy appears for high magnetic fields between the directions in the basal plane. Multi-step metamagnetic processes appear. In the both phases, the χ - T behavior suggests the existence of component-separated magnetic transitions. The ab -component of magnetic moments orders at the higher transition temperature T N1 for the P-phase compound, which is contrast to the I-phase behavior; the c -component orders firstly at T N in the I-phase. The crystalline electric field analysis was made, and the CEF effects explain the different of magnetic anisotropy between the both phases.

Magnetic measurements on pseudoternary compounds Ho1-xGdxRh2Si2, which substitute Gd having no quadrupole for Ho, were performed. They exhibit a successive component-separated magnetic transition; the c- and ab-components of magnetic moments independently order at different temperatures TN1 and TN2, respectively. The partial ordered state, a frustration appears for TN1 >T > TN2: for the phase II in the magnetic phase diagrams. In the ordered phase, step-like metamagnetic processes appear for TN2 > T; two-step ones appear along the [001] and [100] directions, and a one-step one appears along the [110] direction. The B-T magnetic phase diagrams were constructed. There are six, four and three ordered phases in the B001-T, B100-T and B110-T phase diagram, respectively. Two diagrams of the basal plane directions, B100-T and B110-T, resemble each other. Some interesting or peculiar phase boundaries appear. The Gd composition x dependence of transition temperatures is determined. The transition temperatures TN1 and TN2 increase with increasing x. The x-dependency of TN1 is well scaled by the de Gennes factor: (g-1)2J(J+1) whereas the transition of TN2 is not scaled. Some magnetic features declare that quadrupole interactions play an important role in this compound system.

Magnetic studies were performed on PrPd2Si2 single crystals which crystallize in the tetragonal ThCr2Si2-type structure. The temperature dependence of the magnetic susceptibility indicates that the compound orders antiferromagnetically at temperatures below T N = 3.2 K. The transition was confirmed by specific heat measurements. Magnetization measurements at fields up to 18 T show that the easy magnetization direction is the [100] direction in the basal plane. In the magnetization process, five or four metamagnetic transitions appear; the process is a five (four)-step metamagnetic one. The [110] magnetization process is a three-step one. A strong magnetic anisotropy between the [100] and [110] directions is observed within the basal plane for high magnetic fields. Along the hard magnetization direction of the c-axis, a metamagnetic transition appears. The B [100] − T phase diagram was constructed. A magnetic anisotropy between the [100] and [001] directions is also strong. These behaviors are discussed based on an analysis of crystalline field effects.

Measurements of the magnetization and the specific heat were performed on a PrRh2 single crystal. A strong magnetic anisotropy with the easy magnetization direction of the c-axis is observed. Four anomalies appear in the temperature dependence of magnetic susceptibility along the c-axis; a cusp at TN=52 K, a high peak at T3=38 K, a shoulder at T2=33 K and a small peak at T1=4 K are observed, indicating magnetic transitions. The specific heat also shows four anomalies at the temperatures where the magnetic anomalies appear, confirming the occurrence of successive magnetic transitions. A clear two-step metamagnetic process appears along the easy magnetization direction of the c-axis at low temperatures. The magnetization in the first step is almost constant and is corresponds to (1/5) Ms (Ms: saturation magnetization), indicating that this field-induced phase has a long period and a stable magnetic structure. A metamagnetic process is hypothesized on the basis of the magnetic structure. The B001 − T phase diagram is constructed.

The magnetic measurements in detail, especially high field magnetic measurements up to 45 T, have been performed on a TbPd2Ge2 single crystal. The compound shows an antiferromagnetic ordering below T N =14 K. High field magnetization shows that the magnetic easy direction is the [110] direction in the basal plane. The easy magnetization is saturated above about 25 T at 1.3 K and reaches 9.0 μB/f.u. Multi-step metamagnetic processes appear within the basal plane; that is, three-step and five-step metamagnetic processes appear along the [110] and [100] directions, respectively. The [001] magnetization process is a one-step metamagnetic one. All transitions persist up to near T N . The B 100–T and B 110–T magnetic phase diagrams were constructed, where there are five and three ordered phases, respectively. The crystalline electric field effects were examined. On the basis of the effects, the magnetization behavior has been discussed.

The cavitation surge is a kind of instability phenomenon generated in a liquid rocket engine, and it is known that when the inlet pressure of the turbopump of the engine is decreased, the frequency of cavitation surge continuously varied. On the other hand, it was observed in a turbopump test conducted in JAXA that the frequency of cavitation surge discontinuously decreased when the inlet pressure was decreased. Aiming at explaining this curious phenomenon, we conducted the linear analysis using the frequency-domain method and found that this phenomenon was a kind of self-excited vibration coupling the cavitation characteristics with the acoustic resonance of the inlet pipeline. However, the linear analysis could not simulate the phenomenon that a frequency of standing wave changed to the other mode at a certain inlet pressure. Therefore, we conducted the nonlinear analysis using the one-dimensional time-domain method. As a result, it was found that when the inlet pressure was decreased, the damping effect became larger in the higher frequency oscillation because of nonlinear factors. Consequently, the oscillation of higher frequency was intensely weakened and the oscillation of lower one appeared instead.

The magnetic measurements have been performed for high fields up to 18 T and low temperatures down to 0.5 K on the single crystal compound ErCu2Si2. In the temperature dependence of magnetic susceptibility, two anomalies are seen at TN=1.51 K and Tt=0.97 K which is corresponding to an antiferromagnetic ordering temperature and may come from a change of magnetic structure. Low temperature magnetization shows a metamagnetic transition around 0.4 T along the easy magnetization direction of [001]. The magnetization is almost saturated above 3 T and reaches 8.8μB/f.u. at 18 T. A metamagnetic transition appears around 0.5 T in the basal plane magnetization processes as well. The anisotropy within the basal plane is fairly large for high fields. These behaviors have been explained from crystalline electric field effects and magnetic interaction in terms of molecular field.

High field magnetization up to 18 T and magnetic susceptibility measurements have been carried out on a PrRh2Si2 single crystal. The anomalously high Neel temperature of 70 K is confirmed. A strong uniaxial magnetic anisotropy with the easy c-axis is evidenced. A sharp metamagnetic transition appears at 16 T in the easy c-axis magnetization process while magnetization in the basal plane is very small and the curve is linear. The saturation moment obtained is 3.1μB. Crystalline electric field (CEF) effects have been analyzed to discuss the magnetic behaviors.

We report the results of a room-temperature investigation of the thermoelectric and the dilatometric properties of a heavy fermion system YbPd 2 Si 2 (itterbium–palladium–silicon, 1–2–2) at high pressure P up to 22 GPa; YbPd 2 Si 2 is a less-studied representative of the RM 2 X 2 family (R=Ce, Yb, U; M=transition metal; X=Si, Ge) with the tetragonal ThCr 2 Si 2 -type structure of the I 4/ mmm space group. Around P ∼6±0.5 GPa, a phase transition in Yb–Pd–Si was registered by the drastic changes in the pressure dependencies of the electrical resistance R , the thermopower (Seebeck effect) S , a temperature difference along a sample Δ T , and a sample's thickness Δ x (related to compressibility). Both a nature of the found phase transition and a presumable P – T phase diagram of YbPd 2 Si 2 are discussed.

Effects of pressure on the physical properties are very important for understanding highly correlated electron systems, in which pressure-induced attractive phenomena such as superconductivity and magnetically ordered non-Fermi liquid have been observed. Up to now, many scientists have developed a lot of high pressure apparatus for each purpose. In this paper, we present the very small “palm cubic-anvil high-pressure apparatus” for precise electric transport measurements under high pressure up to 8 GPa. The most outstanding characteristic of this pressure cell is its compactness. This cell enables us to measure absolute values of electrical resistivity, magneto-resistance and Hall coefficient at various temperatures. The details of our palm cubic high-pressure apparatus are introduced, and some neutron experimental results at room temperature are discussed.

Photoluminescence properties of Eu-implanted AlGaN with whole Al content are investigated. Strong photoluminescence (PL) lines attributed to 5D0 - 7Fj transitions of Eu3+ are observed from Eu-doped AlGaN with whole Al content. The PL intensity becomes maximum around Al content of x = 0.2. From the results of time-resolved PL, the decay time of Eu3+-related PL decreases with increasing Al content. The intensity enhancement effect of Eu3+-rerated luminescence by AlGaN is mainly due to the improvement of energy transfer efficiency rather than the improvement of transition probability of Eu3+ by changing the crystal field. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Effects of Al composition on luminescence properties corresponding to Tb 3+ inner level transitions are investigated. When the Al composition is larger than 0.3, luminescence corresponding to 5 D 4 - 7 F J (J = 3, 4, 5, 6) transitions is observed at room temperature, while 5 D 3 - 7 F J transition such as 5 D 3 - 7 F 5 can be observed only at low temperature. As the Al composition increases, the luminescence intensity is increased super linearly at first, and then linearly increased. Thermal quenching of luminescence intensity is dramatically improved as increasing the Al composition. Major effect of AlGaN is well explained by reduction of energy-back-transfer process.

A micro-pressure cell has been developed for measurements of specific heat and magnetization by using a commercial SQUID magnetometer. This small piston-cylinder device can be used up to 2 GPa. In this paper, we report on the efficiency of our micro-cell and present some results of the pressure effect on the magnetic and thermal properties of CeAg.

Recessed-gate GaN metal-oxide-semiconductor field-effect transistors with a double-insulator gate configuration demonstrate 10-MHz switching operation of which delay time is

Er ions are introduced into Al x Ga 1-x N (0 ≤ x ≤ 1) by ion implantation to investigate the effect of Al composition on the luminescence properties of 4f n inner-shell transitions of Er 3+ . Strong and sharp emission peaks attributed to the 4f-4f transition of Er 3+ are observed in ultra-violet and blue region (400-550 nm) from the samples with AlN molar fraction of x > 0.3. These photoemissions are assigned as 2 P 3/2 - 4 I 15/2 , 2 P 3/2 - 4 I 13/2 , 2 P 3/2 - 4 I 11/2 , and 2P 3/2 - 4 H 11/2 transitions, and the 408 nm emission, corresponding to 2 P 3/2 - 4 I 13/2 transition, is the strongest in the present work. As increasing the Al composition, the intensity of Er 3+ -related emissions is rapidly increased and the thermal quenching properties is also improved.

The magnetic characteristics of the single crystal compound TbCu 2 Ge 2 have been studied by magnetic susceptibility and magnetization measurements. The susceptibility shows two anomalies at T N =12.3 K and T t =9.3 K. The magnetic easy direction is the [1 1 0] direction in the basal plane. The magnetization along the easy direction in the basal plane shows a multi-step (at least four steps) metamagnetic process. No significant change of the process is observed at T t . A one-step metamagnetic transition appears around 17 T in the hard c -axis magnetization process. This transition persists above T N up to 25 K where the susceptibility shows a broad peak. The origin is unsolved yet.

High performance enhancement-mode m -plane AlGaN/GaN heterojunction field-effect transistors were reported in this letter. +3 V threshold voltages, 230 mA/mm of maximum drain-source current (Ids(max)), and 58 mS/mm of maximum transconductance (gm(max)) were obtained. High Ids(max) and gm(max) were due to the regrown n+-GaN contact layer. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The measurements of the electrical resistivity ρ and the thermopower S of single crystal EuCo2P2 have been performed at temperatures from 1.5 to 300 K under hydrostatic pressures up to 3 GPa and in magnetic fields up to 10 T. The temperature dependences of ρ and S show drastic changes at a critical pressure Pc, which indicates a large modification of the electronic structure around the Fermi level due to the valence transition from Eu to Eu. In the low-pressure phase with magnetic Eu and nonmagnetic Co, the magnetic field dependences of ρ and S show sudden decrease at B ≈ 7 T, implying a metamagnetic transition. On the other hand, no drastic change in ρ(B) and S(B) curves is observed in the high-pressure phase with nonmagnetic Eu and magnetic Co.

Magnetic characteristics of a DyPd2Si2 single crystal with the ThCr2Si2-type structure have been studied from measurements of magnetic susceptibility (T) and magnetization M(B). It was found that DyPd2Si2 orders antiferromagnetically below TN = 9.2 K with the basal-plane [100] axis being the easy magnetization direction at high magnetic fields. Upon increasing magnetic field, the [100] magnetization curve exhibits at least six metamagnetic transitions at 0.2, 1.8, 3.0, 3.7, 4.2 and 6.1 T before reaching the saturation magnetization Ms = 10 B. Five metamagnetic transitions were detected on decreasing fields. For the [110] magnetization process, three metamagnetic transitions were evidenced. In contrast, the M(B) curve along the [001] axis, which is the hard magnetization direction, displays no metamagnetic transition; it shows a monotonous increase with a concave curvature up to 18 T. Finally, we constructed a comprehensive B100-T magnetic phase diagram consisting of six magnetic ordered phases.

We have performed pressure-dependent electrical resistivity measurements of a single crystal Ce 2 Pd 3 Si 5 , which is an antiferromagnetic Kondo lattice compound, at pressures up to 9.5 GPa and at temperatures down to ∼ 0.4 K . As the pressure is increased, the Neel temperature T N deduced from the temperature dependence of resistivity decreases steeply above 4.8 GPa and disappears at P ⩾ 8.6 GPa . Both A and ρ 0 values in Fermi liquid law ρ = ρ 0 + AT 2 at low temperature region increase abruptly above 4.8 GPa and exhibit a plateau at ∼ 9 GPa . These results suggest that non-magnetic state could be formed at P ⩾ 8.6 GPa and that possible quantum critical point might exist at pressures around 9 GPa in this compound. However, there is no sign of superconductivity in resistivity data at the lowest temperature we studied around the possible QCP.

Electrical resistivity measurements have been performed on the heavy fermion superconductor PrOs 4 Sb 12 between 0.3 and 300 K at pressures up to 9.8 GPa. Zero resistivity due to superconducting state was observed at all pressures up to P = 9.8 GPa. With increasing pressure up to 2.0 GPa, superconducting transition temperature T c was linearly shifted to lower temperature at a rate of − 0.16 K / GPa . Effect of pressure on T c became smaller on further pressurization, following that the value of T c was saturated to a constant value of 1.3 K at high pressure. While, the upper critical field H c 2 was strongly suppressed by increasing pressure. H c 2 at 9.8 GPa estimated from the onset temperature of superconducting transition was 0.91 T at 0.5 K.

The ferromagnetic compound Fe2P shows a first-order paramagnetic to ferromagnetic transition at TC=209 K. To investigate the magnetic properties of this compound under high pressures above 3 GPa, it has been tried to measure the magnetization using a diamond anvil type high-pressure apparatus by MPMS (quantum design). As the results of trial and error, we have succeeded to obtain the data with sufficient precision to understand the substantial behavior of the compound even under considerable high pressures above 5.0 GPa.

Enhancement-mode GaN-HEMT devices with a newly developed recessed-gate structure were fabricated. These devices were capable of operating at up to 30 MHz switching. A wireless power transmission (WPT) was adopted for a potential application of these GaN devices, because high-frequency (f) switching devices are expected to improve the power-transfer efficiency (η) of the WPT. A GaN-based E-class amplifier WPT system achieved 10W output power and η =63.5 % under the operating conditions of f =13.56 MHz, duty=50%, and a load resistance of 10Ω.

The need for large-scale electronic structure calculations arises recently in the field of material physics and efficient and accurate algebraic methods for large simultaneous linear equations become greatly important. We investigate the generalized shifted conjugate orthogonal conjugate gradient method, the generalized Lanczos method and the generalized Arnoldi method. They are the solver methods of large simultaneous linear equations of one-electron Schr\"odinger equation and maps the whole Hilbert space to a small subspace called the Krylov subspace. These methods are applied to systems of fcc Au with the NRL tight-binding Hamiltonian (Phys. Rev. B {\bf 63}, 195101 (2001)). We compare results by these methods and the exact calculation and show them equally accurate. The system size dependence of the CPU time is also discussed. The generalized Lanczos method and the generalized Arnoldi method are the most suitable for the large-scale molecular dynamics simulations from the view point of CPU time and memory size., Comment: 13pages, 7figures

The pressure dependence of resistivity for the checkerboard-type charge-ordered (CO) molecular conductor $\ensuremath{\beta}\text{\ensuremath{-}}{(meso\text{-DMBEDT-TTF})}_{2}{\text{PF}}_{6}$ has been investigated. Under the low pressure of 0.6 kbar, the temperature of resistivity minimum $({T}_{\text{min}})$ falls from 90 K at an ambient pressure to 67 K, and after the resistivity has been increased, the superconducting (SC) transition is observed at 4.6 K. By applying magnetic field, the SC state is suppressed and the large positive magnetoresistance (MR) is demonstrated below ${T}_{\text{min}}$ in the CO state. Since the positive MR was observed even in the metallic state under high pressures, the summarized pressure-temperature $(P\ensuremath{-}T)$ phase diagram reveals that the SC state neighbors to the CO-insulating and charge-fluctuated metallic states.

The results of a comprehensive study of the structural, magnetic, and magnetotransport properties of the Heusler compounds ${\text{Ru}}_{2\ensuremath{-}x}{\text{Fe}}_{x}\text{CrSi}$ are presented. The Fe-rich compounds $(x\ensuremath{\ge}1.5)$ exhibit a usual ferromagnetic transition. The Ru-rich compound $(x=0.1)$ does not show ferromagnetism but exhibits a peak in magnetic susceptibility at ${T}_{N}^{\ensuremath{\ast}}=30\text{ }\text{K}$. Nevertheless, specific-heat measurements show that there is no antiferromagnetic transition at ${T}_{N}^{\ensuremath{\ast}}$ nor at any other temperatures. With further decreasing temperature strong irreversible behavior occurs below a temperature ${T}_{g}$. It is proposed that these results can be interpreted as successive spin-glass transitions at ${T}_{N}^{\ensuremath{\ast}}$ and ${T}_{g}$. The compounds with intermediate $x$ ($=0.3$ and 0.5) are found to be ferromagnetic. Both the saturation magnetization and the Curie temperature ${T}_{C}$ increase with increasing $x$. However, being different from the Fe-rich compounds, hysteresis of the magnetization is observed and this suggests that the ferromagnetism has glassy character. In lower-temperature range fairly large negative magnetoresistance are observed. These results are suggestive of a magnetically inhomogeneous ferromagnetic state, that is, the formation of ferromagnetic clusters.

A GW approximation (GWA) method named $\text{U}+\text{GWA}$ is proposed, where we can start GWA with more localized wave functions obtained by the local spin-density approximation $(\text{LSDA})+\text{U}$ method. Then GWA and $\text{U}+\text{GWA}$ are applied to MnO, NiO, and ${\text{V}}_{2}{\text{O}}_{3}$ in antiferromagnetic phase. The band gaps and energy spectra show excellent agreement with the experimentally observed results and are discussed in detail. The calculated width of $d$ bands of ${\text{V}}_{2}{\text{O}}_{3}$ is much narrower than that of the observed one which may be a mixture of ${t}_{2g}^{2}$ multiplet and single-electron ${t}_{2g}$ level. GWA or $\text{U}+\text{GWA}$ does not work also in the paramagnetic phase of ${\text{V}}_{2}{\text{O}}_{3}$ and the reason for this is clarified. The method of the unique choice of on-site Coulomb interaction is discussed in detail. The criterion for whether we should adopt GWA or $\text{U}+\text{GWA}$ is discussed and is assessed with the help of the off-diagonal elements of the self-energy.

The pressure ($p$) -- temperature ($T$) phase diagram for microscopic magnetism in the multiferroic compound HoMn$_{2}$O$_{5}$ was established using neutron diffraction measurements under a hydrostatic pressure up to 1.25 GPa. At ambient pressure, incommensurate--commensurate--incommensurate magnetic phase transitions occur successively with decreasing temperature. Upon applying pressure, the incommensurate phase at the lowest temperature almost decreases and the commensurate phase appears. The $p$ -- $T$ phase diagram established shows excellent agreement with the recently reported $p$ -- $T$ dielectric phase diagram, where ferroelectricity is induced by applying pressure. We also found that the $p$ -- $T$ magnetic phase diagram is quite similar to the previously obtained magnetic field-temperature phase diagram., Comment: 5 pages, 5 figures, to be published in J. Phys. Soc. Jpn

The electronic structure of $A$-type antiferromagnetic insulator $\mathrm{La}\mathrm{Mn}{\mathrm{O}}_{3}$ is investigated by the GW approximation. The band gap and spectrum are in a good agreement with experimental observation. The lifetime of electrons in conduction bands is much shorter than that of holes in valence bands. The insulator-to-metal transition with antiferromagnetic-to-ferromagnetic transition with photocarrier injection is attributed to the characteristic properties of excited electron states in $A$-type antiferromagnetic perovskite systems. The onsite $d\text{\ensuremath{-}}d$ Coulomb interaction is strongly screened at the low energy region by mobile ${e}_{g}$ electrons.

Atomic disorder is investigated for B2- and Heusler-phase CoFe1-xAlx alloys quenched from various temperatures by X-ray diffraction measurements. In the B2-phase region, with increase in quenching temperature, atomic disorder on the Co-site (Co-type disorder) proceeds for x=0.30 but not for x=0.70. In the Heusler-phase region (x=0.45, 0.50 and 0.55), atomic disorder between the Fe- and Al-sites (Fe-Al-type disorder) mainly proceeds. A relation between the magnetic behavior obtained in our previous work and the atomic disorder is examined. As a result, it is found that the Co-type disorder leads to a reduction of the magnetic moment in the B2-phase alloys and that the Fe-Al-type disorder does not significantly affect the magnetic behavior in the Heusler-phase alloys.

Magnetic behavior in Co-based Heusler alloys Co2MnZ (Z=Si, Ge, Sn) is investigated as a function of quenching temperature. The mean magnetic moment decreases with increase in quenching temperature in Co2MnSi and Co2MnGe while it remains almost constant in Co2MnSn. Relation between the magnetic behavior and the atomic disorder is discussed.The results of the lattice constant and the electrical resistance measurements are also reported.

Temperature dependence of time-resolved photoluminescence (PL) properties for rare-earth ions (REIs: Eu, Tb, and Er) implanted AlxGa1-xN (x=0∼1) is investigated. Thermal quenching for RE-related PL becomes small when increasing the Al contents. The PL decay time of REIs used in the present work becomes shorter when increasing the temperature and/or PL peak energy. The temperature dependence of PL intensity and the decay time are analysed by assuming phonon assisted energy-back-transfer model, in which the energy in REIs escape to trap levels. From the results, the improvement of PL properties can be well explained by the model, in which the activation energy for energy-back-transfer process is increased as increasing the Al contents.

We have performed the electrical resistivity measurements on Ce 2 RhIn 8 in the temperature range 0.3–300 K and observed zero-resistance state at ambient pressure on several samples. We have performed synchrotron X-ray diffraction experiment on single crystal of Ce 2 RhIn 8 to investigate relation between superconductivity and crystal structure. Superlattice reflections were observed with modulation wave vector q ∼(0, 0, 1/8) on the superconducting samples at room temperature.

Electrical resistivities of YbMn 2 Ge 2 were measured at several pressures in a temperature range from 2 K to room temperature. In low temperature region below 100 K, temperature dependence of the resistivity shows significant change between 2.0 and 4.0 GPa. Under 4.0 GPa, anomalies of the resistivity were observed at ( T t 3 ∼ ) 21.6 K and ( T t 4 ∼ ) 7.1 K. There is a fair possible that they originated from novel magnetic phase transitions of Yb or Mn sublattice. With increasing pressure, T t 4 increases linearly. In contrast to the pressure dependence of T t 4 , T t 3 decreases linearly.

SmCoIn 5 crystallizes in the tetragonal HoCoGa 5 type structure. This type of crystal structure have attracted much attention because new heavy-fermion superconductivity with very high superconducting transition temperature T c = 18.5 K was discovered in PuCoGa 5 . It is expected that Sm has a similar ground state to Pu compounds. Thus we have measured the electrical resistivity on a single crystal of SmCoIn 5 using a cubic anvil pressure cell at temperature 2–300 K under high pressure from 2 to 8 GPa. The value of T N that was 11.9 K at ambient pressure in SmCoIn 5 increased to 13.2 K at P = 2 GPa. Above 2 GPa, It decreased monotonously with increasing pressure and was 12.6 K at 8 GPa. It may be thought that the 4 f electrons in SmCoIn 5 are more localized than 5 f electrons in PuCoGa 5 .