We present ALMA detection of the [O iii] 88 μm line and 850 μm dust continuum emission in a Y-dropout Lyman break galaxy, MACS0416_Y1. The [O iii] detection confirms the object with a spectroscopic redshift to be z = 8.3118±0.0003. The 850 μm continuum intensity (0.14 mJy) implies a large dust mass on the order of 4×106M⊙. The ultraviolet-to-far infrared spectral energy distribution modeling, where the [O iii] emissivity model is incorporated, suggests the presence of a young (τage ≍ 4 Myr), star-forming (SFR ≍ 60M⊙yr−1), and moderately metal-polluted (Z ≍ 0.2Z⊙) stellar component with a stellar mass of 3 × 108M⊙. An analytic dust mass evolution model with a single episode of star formation does not reproduce the metallicity and dust mass in ≍ 4 Myr, suggesting an underlying evolved stellar component as the origin of the dust mass.

Pneumococcal serotype replacement is an important issue after the introduction of pneumococcal conjugate vaccine (PCV) in children. After the introduction of 13-valent PCV, the incidence of invasive pneumococcal diseases (IPD) caused by Streptococcus pneumoniae serotype 12F (Sp12F) have increased in some countries; however, an outbreak of Sp12F has not reported in the post-13-valent PCV era. We experienced a local outbreak of Sp12F during March through May 2016 in Tsuruoka city, Japan after the introduction of 13-valent PCV in 2013. The IPD patients were two children and seven adults, three of whom died with a rapid disease progress. Although the clear transmission route was not determined, eight of the nine patients (89%) had close contact with children, which suggests that transmitted colonisation of Sp12F among children and adults might be the source of transmission. Continuous monitoring of IPDs, along with the determination of pneumococcal serotypes, is warranted in the post–13-valent PCV era. New IPD control strategies may be needed if this fatal outbreak continues to occur.

We discuss discrete stochastic processes with two independent variables: one is the standard symmetric random walk, and the other is the Poisson process. Convergence of discrete stochastic processes is analysed, such that the symmetric random walk tends to the standard Brownian motion. We show that a discrete analogue of Ito’s formula converges to the corresponding continuous formula.

In the previous investigation, piezoelectric properties of the ‘Aligned-type’ in which the piezoelectric-ceramic particles are formed in linear aggregates in the rubber, remarkable piezoelectric properties were confirmed. In this investigation, to further enhance the piezoelectric properties of the Aligned-type, the influence of the matrix properties was investigated. The properties on which we focused were the dielectric constant and the Young’s modulus. Four kinds of matrix materials whose dielectric constant and Young’s modulus are different from each other; Silicone gel, Silicone rubber, Urethane rubber and Poly-methyl-methacrylate were investigated. As a result of measurement of the piezoelectric strain constant d 33 of the Aligned-Type, it was confirmed that though the influence of the dielectric constant of the matrix material was small, the lower the Young’s modulus of the matrix was, the higher d 33 was.

We show that high-efficiency and low-degradation hydrogenated amorphous silicon (a-Si:H) p-i-n solar cells can be obtained by depositing absorber layers in a triode-type plasma-enhanced chemical vapor deposition (PECVD) process. Although the deposition rate is relatively low (0.01-0.03 nm/s) compared to the conventional diode-type PECVD process (∼0.2 nm/s), the light-induced degradation in conversion efficiency of single-junction solar cell is substantially reduced (Δη/ηini∼10%) due to the suppression of light-induced metastable defects in the a-Si:H absorber layer. So far, we have attained an independently-confirmed stabilized efficiency of 10.11% for a 220-nm-thick a-Si:H solar cell which was light soaked under 1 sun illumination for 1000 hours at cell temperature of 50°C. We further demonstrate that stabilized efficiencies as high as 10% can be maintained even when the solar cell is thickened to >300 nm.

Monitor of All-sky X-ray Image (MAXI) on board International Space Station is capable of observing gamma-ray bursts (GRBs) and sending notices of GRBs or other transient events, using real time connection to the ground. MAXI observed 32 GRBs or short X-ray transients as of the end of September 2012. Among them, eleven events were simultaneously detected by other satellites. The observed rate of the MAXI GRBs is about one event per month. This rate is comparable to a past observation with larger effective area and larger field of view. The fact indicates that MAXI has better sensitivity to observe GRBs because of low background. The distribution of the spectral hardness of MAXI GRBs is similar to the results of a past instrument, which is sensitive to similar energy range.

Periodically textured back reflectors with hexagonal dimple arrays are applied to thin-film microcrystalline silicon (μc-Si:H) solar cells for enhancing light trapping. The period and aspect ratio of the honeycomb textures have a big impact on the photovoltaic performance. When the textures have a moderate aspect ratio, the optimum period for obtaining a high short circuit current density (J SC ) is found to be equal to or slightly larger than the cell thickness. If the cell thickness exceeds the texture period, the cell surface tends to be flattened and texture-induced defects are generated, which constrain the improvement in J SC . Based on these findings, we have fabricated optimized μc-Si:H cells achieving a high active-area efficiency exceeding 11% and a J SC of 30 mA/cm2.

We have fabricated high-efficiency a-Si/µc-Si tandem solar cells and modules with a very high µc-Si deposition rate using Localized Plasma Confinement CVD to give very high-rate deposition (>2.0 nm/s) of device-grade µc-Si layers. For further progress in productive plasma-CVD techniques, we have studied plasma phenomena by combining newly developed plasma simulation and plasma diagnosis techniques that reveal the importance of non-emissive atomic hydrogen. We also have proposed a model of defective µc-Si formation on highly textured substrates in which the atomic H in plasma is assumed to play an important role. We are also developing a non-vacuum deposition technique that we term “Liquid Si Printing.” A new record conversion efficiency for HIT solar cells of 24.7% has been achieved using a very thin c-Si wafer (Thickness: 98 µm, Area: 102 cm2).

It is difficult to get a real scale image of the solar system through lecture. A scale model is a classical and one of good solutions (e.g. Handa et al.2003, Handa et al.2008). Through this model, people living in or visiting to the city can physically understand the scale of the solar system. This scale gives 1 cm for Earth's diameter and 115 m for 1 AU. However, some gadget is required to make it attractive for public citizens.

The current trends in stimulated Brillouin scattering and optical phase conjugation are overviewed. This report is formed by the selected papers presented in the “Fifth International Workshop on stimulated Brillouin scattering and phase conjugation 2010” in Japan. The nonlinear properties of phase conjugation based on stimulated Brillouin scattering and photo-refraction can compensate phase distortions in the high power laser systems, and they will also open up potentially novel laser technologies, e.g., phase stabilization, beam combination, pulse compression, ultrafast pulse shaping, and arbitrary waveform generation.

For the gate last approach of a high K metal gate scheme used in advanced CMOS technology, various materials were tested as wetting layers to allow Aluminum (Al) gap fill at gate widths of10 to 45 nanometers. In this study, Titanium (Ti) and Cobalt (Co) were investigated as a wetting layer for Al gap fill. It was discovered that Al-Ti and Al-Co alloys were formed during high temperature Al deposition. Alloys were characterized using XRD. Alloy’s impacts on line resistivity and subsequent Al Chemical Mechanical Polish (Al CMP) were also investigated. In addition, a model was established to predict the alloy type and alloy mole% with respect to feature size. The predicted Al mole% by this model correlated very well with 1) line resistivity trend and 2) morphologies. The model also predicted that due to Al lower electro-chemical potential than Ti, Co or its alloys, galvanic corrosion could take place depending on the chemical environment in the Al CMP slurry. Different slurry or cleaning chemical may reduce or increase the risk of galvanic corrosion. The knowledge gained with the help of the model provides clear directions on selection criteria for wetting layers, optimization for deposition processes and Al CMP consumable design to meet the challenges.

Toward complete artificial photosynthesis systems to generate hydrogen and oxygen using visible light and water, we firstly design and fabricate oxygen-generating gel systems using the electrostatic interactions of ionic functional groups and steric effects of a polymer network. By using a graft polymer chain with Ru(bpy)3 2+ units as sensitizers to closely arrange RuO2 nanoparticles as catalyst, the functional groups transmit multiple electrons cooperatively to generate oxygen. In this study, a novel strategy is shown to design a hierarchical network structure using colloidal nanoparticles and macromonomers.

High reliability, low power consumption and high speed laser diodes are required for optical interconnect. We developed 1060nm VCSELs with InGaAs/GaAs strained quantum wells, oxide-confined and double intra-cavity structures for that purpose. As for the power consumption, low power dissipation of 0.14 mW/Gbps at 10 Gbps operation has been achieved. Clear eye openings up to 20 Gbps were confirmed at a low bias current of 5 mA. In the reliability test, accelerated aging tests were performed up to 5,000 hours at 6 mA in three different temperatures, 70 oC, 90 oC and 120 oC. The total number of the VCSELs was 4,898 pcs (approximately 5,000). No failure was observed. Under the normal operating condition of 40 oC and 6 mA, the total device-hours was 7.75×107 hours assuming Ea = 0.35 eV according to Telcordia GR-468-CORE. The random failure rate of 30 FIT with the confidence level (C.L.) of 90 % and 12 FIT with the C.L. of 60 % were estimated. To estimate the wear-out lifetime and the number of FITs, high stressed aging tests with 170 oC and 6 mA were performed. With the acceleration factor of Ea = 0.7 eV in the wear-out failure, the median lifetime was 3,000 hours which was equivalent to 300 years in 40 oC ambient. The FIT numbers due to the wear-out were estimated as 0.3 FIT for 10 years. Compared with the random failure rate of 30 FIT, the wear-out failure rates are considered to be negligible. In the extremely long term aging test with 90 oC and 6 mA, no wear-out trend has been observed in both threshold current and optical power up to 20,000 hours operation. These results indicate that 1060 nm VCSEL is promising light source used in optical interconnect for high performance computers and data centers.

Thermoelectric properties of the Li-doped Cu0.95-x M0.05Li x O (M=divalent metal ion; Mn, Ni, Zn) were investigated at the temperature up to 1273 K. In the doped divalent metal ions, Zn2+ ion was the most effective to reduce the thermal conductivity, and the Ni2+ substitution was preferable to decrease the electrical resistivity. For the Cu0.95-x Ni0.05Li x O sample at x=0.03, the maxima of the dimensionless thermoelectric figure of merit ZT and the power factor P at 1246 K were 4.2×10-2 and 1.6 ×10-4 W/K2m, respectively. The enhancement of the thermoelectric properties of the Li-doped Cu0.95-x M0.05Li x O system was discussed.

We developed the novel pressure-annealing method for fabricating printed low-work function metal patterns and printed metal alloy patterns. The printed diode having various rectification properties was successfully produced by using the printed metal alloy electrode pressure-annealed.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.