A5033388270- Diamond and Carbon-based Materials Research
- Semiconductor materials and devices
- Metal and Thin Film Mechanics
- Electronic and Structural Properties of Oxides
- Force Microscopy Techniques and Applications
- Ion-surface interactions and analysis
- Advanced Polymer Synthesis and Characterization
- High-pressure geophysics and materials
- Mechanical and Optical Resonators
- Block Copolymer Self-Assembly
- Material Dynamics and Properties
- X-ray Diffraction in Crystallography
- Polymer crystallization and properties
- Advanced Materials Characterization Techniques
- Crystallization and Solubility Studies
- Polymer Nanocomposites and Properties
- Glycosylation and Glycoproteins Research
- Nuclear Physics and Applications
- Advanced Surface Polishing Techniques
- Atomic and Subatomic Physics Research
- Carbohydrate Chemistry and Synthesis
- Boron and Carbon Nanomaterials Research
- Magnetism in coordination complexes
- Advanced Fiber Laser Technologies
- Enzyme Production and Characterization
National Institute for Materials Science
2016-2025
Ibaraki University
2013-2024
Kyowa Kirin (Japan)
1998-2023
University of Tokyo Hospital
2023
National Institute of Advanced Industrial Science and Technology
2005-2021
University of Tsukuba
2003-2017
High Energy Accelerator Research Organization
2017
The Graduate University for Advanced Studies, SOKENDAI
2017
Okinawa Institute of Science and Technology Graduate University
2017
Japan Science and Technology Agency
2001-2016
We report the realization of an ultraviolet light–emitting diode with use a diamond pn junction. The junction was formed from boron-doped p-type layer and phosphorus-doped n-type grown epitaxially on {111} surface single crystalline diamond. exhibited good characteristics, at forward bias about 20 volts strong light emission 235 nanometers observed attributed to free exciton recombination.
An n-type semiconducting diamond thin film was obtained by microwave enhanced plasma chemical vapor deposition using phosphine (PH3) as a dopant source. A homoepitaxial with thickness of about 300 nm grown on the {111} surface type Ib variety concentrations. Over wide range concentrations (PH3/CH4: 1000–20 000 ppm), conduction confirmed Hall-effect measurements. The activation energy carriers 0.43 eV. Hall mobility 23 cm2/V s has been at around 500 K for 1000 ppm sample. No significant...
We report the detection and polarization of nuclear spins in diamond at room temperature by using a single nitrogen-vacancy (NV) center. use Hartmann-Hahn double resonance to coherently enhance signal from spin while decoupling noisy spin-bath, which otherwise limits sensitivity. As proof-of-principle we: (I) observe coherent oscillations between NV center weakly coupled spin, (II) demonstrate bath cooling prolongs coherence time sensor more than factor five. Our results provide route...
Objectives Prevotella copri is considered to be a contributing factor in rheumatoid arthritis (RA). However, some non-Westernised countries, healthy individuals also harbour an abundance of P. the intestine. This study investigated pathogenicity RA patient-derived ( ) compared with control-derived HC ). Methods We obtained 13 P . strains from faeces patients and controls. Following whole genome sequencing, sequences were compared. To analyse arthritis-inducing ability , we examined two...
Abstract Diamond holds the highest figure‐of‐merits among all known semiconductors for next‐generation electronic devices far beyond performance of conventional semiconductor silicon. To realize diamond integrated circuits, both n‐ and p‐channel conductivity are required development complementary metal‐oxide‐semiconductor (CMOS) devices, as those established However, CMOS has never been achieved due to challenge in n‐type channel MOS field‐effect transistors (MOSFETs). Here, electronic‐grade...
Diamond thin films have been grown epitaxially on high-pressure synthesized cubic boron nitride (c-BN) particles by using dc plasma chemical vapor deposition. At the early growth stage of film c-BN{111} surfaces, island structure is observed and number density islands about 1011 cm−2. The coalescence are also found scanning electron microscopy observation. continuous obtained at thickness 2000 Å surface rather smooth. Raman peak epitaxial diamond shows shift toward lower wave due to tensile...
Members of the Fusarium graminearum species complex are important cereal pathogens worldwide and belong to one at least nine phylogenetically distinct species. We examined 298 strains F. collected from wheat or barley in Japan determine trichothecene chemotype. Phylogenetic analyses species-diagnostic polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLPs) revealed presence differential distribution sensu stricto (s. str.) asiaticum Japan. s. str. is predominant north,...
Using a combined ultra-small-angle and small-angle scattering (CSAS) method of neutrons X-rays, we investigated hierarchical structures carbon black (CB) highly loaded in polyisoprene (PI) poly(styrene-random-butadiene) copolymer (SBR) under mechanical field (defined respectively as CB/PI CB/SBR) well toluene sonic CB/toluene). In order to analyze each structure level comprising the CB from CSAS profiles, employed unified Guinier/power-law approach proposed by Beaucage (J. Appl. Cryst. 1995,...
Spins of negatively charged nitrogen-vacancy (NV${}^{\ensuremath{-}}$) defects in diamond are among the most promising candidates for solid-state qubits. The fabrication quantum devices containing these spin-carrying requires position-controlled introduction NV${}^{\ensuremath{-}}$ having excellent properties such as spectral stability, a long spin coherence time, and stable negative charge state. Nitrogen ion implantation annealing enable positioning qubits with high precision, but to date,...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOrdered Structures of Block Copolymer/Homopolymer Mixtures. 5. Interplay Macro- and Microphase TransitionsSatoshi Koizumi, Hirokazu Hasegawa, Takeji HashimotoCite this: Macromolecules 1994, 27, 22, 6532–6540Publication Date (Print):October 1, 1994Publication History Published online1 May 2002Published inissue 1 October 1994https://pubs.acs.org/doi/10.1021/ma00100a044https://doi.org/10.1021/ma00100a044research-articleACS PublicationsRequest reuse...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOrdered structure in blends of block copolymers. 1. Miscibility criterion for lamellar copolymersTakeji Hashimoto, Komei Yamasaki, Satoshi Koizumi, and Hirokazu HasegawaCite this: Macromolecules 1993, 26, 11, 2895–2904Publication Date (Print):May 1, 1993Publication History Published online1 May 2002Published inissue 1 1993https://pubs.acs.org/doi/10.1021/ma00063a039https://doi.org/10.1021/ma00063a039research-articleACS PublicationsRequest reuse...
A diamond field emitter array has been fabricated. by Chemical vapor deposition. Diamond was grown on an inverted pyramidal-shape Si substrate followed removal of the substrate. The fabricated placed in a high vacuum pumping system with pressure ∼10−7 Torr and emission current as function anode voltage measured. distance between tungsten surface held constant at 100 μm throughout measurement. As result, larger than 10−4 obtained for 6 kV. linear relationship Fowler–Nordheim plot indicated...
Lightly phosphorus-doped {111} homoepitaxial diamond films have been grown by microwave plasma-assisted chemical vapor deposition under optimized growth conditions. The Phosphorus concentration in the film can be controlled at a low doping level of order 1016cm−3. N-type conductivity with phosphorus concentrations above 1×1016cm−3 is reproducibly confirmed Hall-effect measurements temperature range from 300to873K. highest value Hall mobility room 660cm2∕Vs obtained for 7×1016cm−3.
This investigation focused on the self-assembly of poly(N-isopropylacrylamide)-block-poly(ethylene glycol) (PNIPA-block-PEG) in water. A quasi-living radical polymerization technique including a Ce(IV) ion redox system enabled us to prepare block copolymers with relatively narrow molecular weight distributions. We distinguish five regions phase diagram: transparent sol, opaque gel, and syneresis. By examining extent changes spectroscopic properties fluorescence probe, pyrene, as function...
This paper reports a method that uses humanoid robots as communication medium. There are many interactive under development, but due to their limited perception, interactivity is still far poorer than of humans. Our approach in this limit robots' purpose non-interactive medium and look for way attract people's interest the information convey. We propose using passive-social medium, which multiple converse with each other. conducted field experiment at train station eight days investigate effects
The tetranuclear complex [MnIII2NiII2Cl2(salpa)2] (salpa = N-(2-hydroxybenzyl)-3-amino-1-propanol) has a spin ground state of S 6 and was confirmed to be an SMM based on steplike feature the magnetization hysteresis loop at 0.55 K.
Single-crystal diamond nanowires with well-controlled dimensions are fabricated in batches for nanoelectromechanical system (NEMS). All-single-crystal NEM switches demonstrated using these high reproducibility, controllability, repeated switching, and no sitction. Diamond not only overcome the stiction abrasion problems existing electromechanical switches, but also circumvent shallow doping problem. Detailed facts of importance to specialist readers published as ”Supporting Information”....
With optical/electronic devices of the next generation in mind, we provide a guideline for growth homoepitaxial diamond films that possess higher crystalline quality, chemical purity, and carbon isotopic ratio. A custom‐built microwave plasma‐assisted vapor deposition system was constructed to achieve these requirements. To improve both purity quality films, an advanced condition applied: oxygen concentration ambient. Under this high‐quality diamond, thick film ≥30 μm deposited reproducibly...