A5042018312- Superconducting and THz Device Technology
- Photonic and Optical Devices
- Particle accelerators and beam dynamics
- Terahertz technology and applications
- Integrated Circuits and Semiconductor Failure Analysis
- Calibration and Measurement Techniques
- Thermal Radiation and Cooling Technologies
- Nuclear Physics and Applications
- Radiation Detection and Scintillator Technologies
- Plasma Diagnostics and Applications
- Force Microscopy Techniques and Applications
- Rock Mechanics and Modeling
- Mechanical and Optical Resonators
- Near-Field Optical Microscopy
- Scientific Measurement and Uncertainty Evaluation
- Muon and positron interactions and applications
- thermodynamics and calorimetric analyses
- Gyrotron and Vacuum Electronics Research
- Particle Detector Development and Performance
- Photonic Crystals and Applications
- Semiconductor materials and devices
- Advanced Sensor Technologies Research
- Optical Coatings and Gratings
- Thin-Film Transistor Technologies
- Ion-surface interactions and analysis
National Institute of Advanced Industrial Science and Technology
2014-2024
Tokyo Metropolitan Matsuzawa Hospital
2024
Japan Advanced Institute of Science and Technology
2007-2011
Commonwealth Scientific and Industrial Research Organisation
2010
GFZ Helmholtz Centre for Geosciences
2010
Hitachi (Japan)
1988-2009
International Research Center for Japanese Studies
2008
The University of Tokyo
1997-2007
Tokyo Institute of Technology
2005
Tokyo University of Science
1999-2002
We have realized a high-detection-efficiency photon number resolving detector at an operating wavelength of about 850 nm. The consists titanium superconducting transition edge sensor in optical cavity, which is directly coupled to fiber using approximately 300-nm gap. gap reduces the sensitive area and heat capacity device, leading high resolution 0.42 eV without sacrificing detection efficiency or signal response speed. Wavelength dependent fiber-coupled devices, due interference between...
A novel defect mode is realized in a three-layered structure: left-handed cholesteric liquid crystal (CLC) layer sandwiched between right-handed CLC films (see Figure). The states emerge, and the photonic density of state resonantly enhanced when coincides with edge mode. lasing from this found to show lower threshold value.
Microtextured polydimethylsiloxane sheets exhibit an exceptionally low reflectance of ≲0.0005 across the entire thermal infrared wavelengths while maintaining high resilience.
Emerging immersive high-dynamic range display technologies require not only high peak luminance but also true black levels with hemispherical reflectance below 0.001 (0.1%) to accommodate the wide dynamic of human eye (~105). Such low materials, denoted here as "supreme black," must exhibit near-perfect surface antireflection, extremely in-matrix backscattering, and sufficient optical thickness, which, date, have been achieved by fragile sparse materials. We demonstrate a record-low 0.0002...
The characterization of the excavation-damaged zone (EDZ) around an underground excavation is a major research topic for deep geological disposal medium- to high-level radioactive waste. Rock fracturing because and thermal loading its resultant rock mass permeability change in EDZ are important construction projects long-term safety. A new function predict fractured rocks has been developed added existing fracture mechanics code FRACOD. functions FRACOD have applied extent vicinity tunnel...
High-efficiency photon-number-resolving detectors have been developed using titanium-based transition-edge sensors. Device performances evaluated with respect to the response photon distribution, dark count, and timing jitter. In analysis of statistics, observed detection probabilities were consistent Poisson distributions. From a comparison measured distribution theory, 98% efficiency was deduced at 850 nm. The count probability device is less than <formula formulatype="inline"...
Transition edge sensor microcalorimeters can be used in many optical quantum measurements because of its low dark counts, high efficiency, and resolving power a photon number weak light pulses. In order to increase count rates up few MHz, we have developed titanium transition for the measurements, performances were analysed. Titanium is one ideal superconductor higher temperature lower reflectance at 1.5 wavelength. Our film was fabricated with electron-beam evaporation, showed residual...
We developed a calorimeter for determining absolute terahertz (THz) power. The is based on DC substitution method using an isothermal temperature-control technique. A neutral-density optical filter glass was used as volume absorber, and its THz absorption evaluated by time-domain spectrometer. Highly sensitive measurement of the power experimentally achieved in range from submicrowatt to microwatt level at room temperature. Power continuous-wave source photomixer demonstrated. This expected...
Spectral supralinearity of silicon photodiodes in visible light was investigated. The experimental spectral results were compared with the calculation using a device simulator, PC1D that includes front surface recombination parameters, and these comparison reasonable agreement for photodiode. These show clearly occurs charge density more than 1012 cm-2 included parameters are adequate quantitatively predicting internal quantum efficiency photodiodes.
A prototype positron emission tomography (PET) scanner using CdTe semiconductor detectors was developed, and its initial evaluation conducted. The configured to form a single detector ring with six separated units, each having 96 arranged in three layers. field of view (FOV) size 82 mm diameter. Basic physical performance indicators the were measured through phantom studies confirmed by rat imaging. system-averaged energy resolution timing 5.4% 6.0 ns (each FWHM) respectively. Spatial at FOV...
A model describing spectral supralinearity for a silicon photodiode in the near-infrared region is presented. This theoretical based on internal quantum efficiency of using Shockley-Read-Hall recombination, which depends inner structure parameters photodiodes. Comparing experimental results with calculation results, enables us to quantitatively predict starting power level, shape, and wavelength dependence photodiode. contributes high-accuracy measurements over wide optical ranges various...
The geometric locations of ion traversals in mammalian cells constitute important information the study heavy ion-induced biological effects. We employed a contact microscopy technique, which was developed for boron imaging neutron capture therapy to irradiation by low-energy ions. This method enables simultaneous visualization as relief on plastic track detector, CR-39, and etch pits indicate positions traversals. technique provides visual about traversal, without any specially designed...
Porous nickel-phosphorus (NiP) black surfaces exhibit excellent low reflectance in the visible and near-IR regions. Through use of a model surface morphology composition, was numerically simulated by three-dimensional finite-difference time-domain method to determine origin reflectance. In agreement with experimental results, simulations showed spectrally flat, quite <0.1% over entire visible-near-IR region under certain conditions. The depended strongly on thickness nickel oxide layer...
We present a large-area perfect blackbody sheet, which would offer planar standard radiator for high-precision thermal imager calibration. Polydimethylsiloxane (PDMS) sheets with nano-precision surface micro-cavity structures achieve both ultra-low reflectance (ultra-high emissivity close to unity) over the infrared wavelengths and high durability mechanical contact. The investigation on geometrical parameters of conical micro-cavities, that is, radii aspect ratios (ratio height radius),...
An attenuation calibration system is developed using an isothermal temperature control-type calorimeter for a terahertz (THz) attenuator. This based on power ratio measurement by dc substitution. A highly sensitive achieves simple and accurate at room temperature. Calibration performed metalized-film attenuators 1 THz photomixer as the source. The uncertainties in are evaluated, expanded uncertainty found to be 0.19-0.84 dB (k = 2) range up 12 dB.
We have developed a calorimeter for metrology standard measuring the power of terahertz (THz) waves. Since THz is based on thermal balance between heat produced by waves and direct current (DC), it requires an equivalent factor converting from to DC power. The factor, which defined as ratio efficiency powers, was calculated with simulator finite element method. This estimated be approximately 1 maximum error 0.7 %, implies good equivalence enabling accurate measurement absolute