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A scanning frequency of 350 kHz is demonstrated with a full deflection angle of 95.8 mrad using a KTa1-xNbxO3 (KTN) deflector. To suppress degradation of the deflection angle, the KTN chip is directly glued to metal block electrodes with conductive paste, and the temperature of the deflector is controlled so that the capacitance of the KTN chip remains constant. [ABSTRACT FROM AUTHOR]

We have investigated the mechanism for silicidation by chemical reactions at polycrystalline-Si (poly-Si)/HfO2/Si gate stacks by annealing in ultrahigh vacuum using photoemission spectroscopy and x-ray absorption spectroscopy. Si 2p, Hf 4f, and O 1s high-resolution photoemission spectra have revealed that a Hf-silicide formation starts at as low temperature as 700 °C and that a Hf silicate is also formed at the interface between poly-Si electrodes and HfO2. The metallic Hf silicide is formed at the interface between HfO2 and Si substrates, which changes the band offsets on Si substrates. We have found that poly-Si electrodes promote the interfacial reaction between HfO2 and Si substrates, while the crystallization in a HfO2 layer is independent of the silicide formation. The silicidation mechanism based on photoemission spectra is also confirmed from the thermodynamical analysis considering the Gibbs’ free energy. [ABSTRACT FROM AUTHOR]

A polarisation‐independent optical beam scanner that uses electro‐optic KTa1−xNbxO3 (KTN) crystals has been demonstrated. The polarisation dependence was compensated for by using a pair of KTN beam scanners and a half‐waveplate without any degradation in the performance of either KTN beam scanner. This compensation is the result of a combination of electro‐optic effects consisting of Kerr effects and elasto‐optic effects via the electrostrictive and elastic strains in KTN crystals. [ABSTRACT FROM AUTHOR]

Three‐dimensional (3D) optical coherence tomography (3D‐OCT) has attracted attention for visualising complex structures in the biomedical field. In this reported work, a high‐speed 3D‐OCT system is developed, which is based on a high‐speed swept light source and a Mach‐Zehnder interferometer with a high‐speed photodetector. The light source, incorporating a KTa1–xNbxO3 electro‐optic deflector, operates at a repetition rate of 200 kHz and enables high‐speed data acquisition. As a preliminary study, images of a strawberry's surface have been obtained, two‐ and three‐dimensionally. The 3D‐OCT system has potential for the construction of a four‐dimensional OCT image to dynamically display 3D‐OCT images. [ABSTRACT FROM AUTHOR]

A new light source for swept-source optical coherence tomography (SS-OCT) is presented, namely, an external-cavity LD equipped with a KTN electro-optic deflector. The KTN deflector is unique in being very fast and simultaneously providing an appreciable deflection caused by injected carriers. Being free from mechanical resonance, the 1.3 µm laser exhibits a scanning range of almost 80 nm up to 200 kHz with a ±400 V deflector driving voltage. Preliminary SS-OCT images of a human fingernail and finger skin have been obtained using the swept light source. [ABSTRACT FROM AUTHOR]

In multiferroic materials, luminescence intensities can be direction dependent, i.e., different between the opposite propagating directions of emitted light. However, the effect has not been thought to be used for technological applications, since only small directional asymmetry has been reported so far. Here we show that the effect is robust in multiferroic CuB2O4. The luminescence intensity changes by about 70% between the opposite directions of the emission, which is about 100 times larger than the previously reported values. We demonstrate that such a gigantic directional asymmetry of luminescence can be applied to the imaging of canted antiferromagnetic domains. The observation of the effect and its application to magnetic domain imaging are important for a deeper understanding of light-matter interactions as well as technological applications such as optical reading techniques for magnetic memory devices. [ABSTRACT FROM AUTHOR]

We have investigated band discontinuities and chemical structures of Al2O3 gate insulator films on n-type GaN semiconductor by photoemission and x-ray absorption spectroscopy. It is found that the solid phase epitaxy at the GaN crystal during annealing procedures at 800 °C leads to phase transformation of Al2O3 films from amorphous to crystalline. Changes in crystallographic structures closely correlate with the significant increase in conduction band discontinuity at the Al2O3/GaN interface, which suggests that epitaxial Al2O3 films on GaN semiconductor, free from grain boundaries of Al2O3 polycrystalline, hold the potential for high insulation performance. [ABSTRACT FROM AUTHOR]

1. This study assessed 1) the effects of Paracoccus carotinifaciens supplementation containing high astaxanthin levels on egg production performance and quality, 2) dynamics of carotenoids levels in the egg yolk and 3) taste of astaxanthin-rich egg yolk. 2. Laying hens were fed diets containing different levels of P.carotinifaciens-derived astaxanthin (ASX; 0, 2, 4, 8, or 16 ppm) for 28 d (experiment 1) or a diet containing 16 ppm astaxanthin for 28 d followed by a 0 ppm astaxanthin diet for 28 days (experiment 2). 3. Production performance, egg quality and egg yolk carotenoid levels were examined in experiment 1 (Ex1) and the dynamics of egg yolk carotenoid levels and egg yolk taste in experiment 2 (Ex2). 4. ASX supplementation did not affect production performance or egg quality. ASX levels in the egg yolk became saturated after seven days of 16 ppm supplementation and decreased to less than one-tenth of the saturated levels seven days after supplementation cessation. Supplementation with 16 ppm ASX for 28 d did not affect egg yolk taste. 5. Supplementation resulted in the production of ASX-rich eggs for a brief period without affecting production performance, egg quality or taste. Understanding the time taken for the incorporation of ASX into egg yolks is beneficial for value-added egg production and may help in minimising supplementation costs. [ABSTRACT FROM AUTHOR]