A5012163515- Terahertz technology and applications
- Superconducting and THz Device Technology
- Spectroscopy and Laser Applications
- Photonic and Optical Devices
- Physics of Superconductivity and Magnetism
- Astrophysical Phenomena and Observations
- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Particle Detector Development and Performance
- Astronomy and Astrophysical Research
- Semiconductor Quantum Structures and Devices
- Radio Astronomy Observations and Technology
- Advanced Chemical Sensor Technologies
- Atomic and Subatomic Physics Research
- Astronomical Observations and Instrumentation
- Photonic Crystals and Applications
- Cosmology and Gravitation Theories
- Nuclear Physics and Applications
- Acoustic Wave Resonator Technologies
- Advanced Semiconductor Detectors and Materials
- Dark Matter and Cosmic Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- Astrophysics and Cosmic Phenomena
- Calibration and Measurement Techniques
- Stellar, planetary, and galactic studies
RIKEN
2015-2024
Nippon Soken (Japan)
2011-2024
RIKEN Center for Advanced Photonics
2015-2024
Tohoku University
2014-2024
Photonics (United States)
2016-2024
Nitto RIKEN (Japan)
2005-2020
Saitama University
2012-2019
Graduate School USA
2019
Kyoto University
2019
Tokyo Institute of Technology
2016
We report on the variability of iron K emission line in Seyfert 1 galaxy MCG--6-30-15 during a four-day ASCA observation. The consists narrow core at an energy about 6.4 keV, and broad red wing extending to below 5 which are interpreted as arising from inner parts accretion disk. correlates well with continuum flux whereas weakly anti-correlates. When source is brightest, dominated by core, whilst deep minimum, very weak huge tail appears. However, other times when shows rather rapid...
We present an imaging system designed for use in the terahertz range. As radiation source a backward-wave oscillator was chosen its special features such as high output power, good wave-front quality, stability, and wavelength tunability from 520 to 710 GHz. Detection is achieved with pyroelectric sensor operated at room temperature. The alignment procedure optical elements described, several methods reduce etalon effect that are inherent monochromatic sources discussed. spot size sample...
A label-free biological sensor, which is based on the resonant transmission phenomenon of a thin metallic mesh, proposed in terahertz wave region. By using this we demonstrate highly sensitive detection small amounts protein horseradish peroxidase. For quantitative investigation sensitivity our peroxidase was printed mesh surface by commercial available printer. distinct shift dip frequency observed for 500pg∕mm2 (11fmol) indicating significantly high sensor.
Terahertz spectroscopic images of paraffin-embedded cancer tissues have been measured by a terahertz time domain spectrometer. For the systematic identification tumors, principal component analysis and clustering were applied. In three four samples, tissue was recognized as an aggregate data points in plots. By agglomerative hierarchical clustering, well categorized into other tissues. This method can be also applied to various kinds automatic discrimination plural components imaging.
We discuss the discovery potential of Dark-photons & Axion-Like particles Interferometer in this paper. The apparatus, currently a design and prototyping phase, will probe axion dark matter from Teide Observatory, an environment protected terrestrial microwave sources, reaching Dine-Fischler-Srednicki-Zhitnitsky-like sensitivity range <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mn>25</a:mn><a:mi>–</a:mi><a:mn>250</a:mn><a:mtext> </a:mtext><a:mtext>...
We present the redesign and improved performance of laser terahertz emission microscope (LTEM), which is a potential tool for locating electrical failures in integrated circuits. The LTEM produces an image THz waves emitted when circuit irradiated by femtosecond laser; amplitude proportional to local electric field. By redesigning optical setup improving spatial resolution system below 3 microm, we could extend its application examining large-scale integration As example show pattern field...
A surface-wave sensor based on the resonant transmission characteristics of metal hole arrays is demonstrated in terahertz (THz) region. Since frequency peak a array, which corresponds to surface waves, particularly sensitive refractive index vicinity surface, very small change substances attached can be detected by monitoring spectrum. By attaching layer substance (thickness t < 5 microm) much thinner than wavelength THz wave (lambda(THz) = 1 mm at 0.3 THz) we that existence such amount...
Temperature-dependent terahertz (THz) absorption spectra of poly(3-hydroxyalkanoate)s (PHAs) were measured by using a Fourier transform far-infrared (FT-FIR) spectrometer and THz time-domain over temperature range 10 K to 465 with liquid helium cryostat heating cell. Clear differences observed between the crystalline amorphous polyhydroxybutyrate (PHB), indicating that peaks in originated higher-order conformation PHB. The polarization stretched PHB sample measured, direction vibrational...
Recently, terahertz wave imaging has been shown to have potential in medical and biological applications. However, absorption by liquid water tissues hinders the measurement of thick samples. In this study, porcine tissue was frozen temperatures below −33 °C prevent absorption. Consequently, striated muscle adipose could be clearly distinguished time-domain spectra owing difference absorbance values refractive indices. We demonstrated two-dimensional map pulse delay, which shows spatial...
Using the high penetrability of terahertz waves and characteristic absorption spectra in this frequency range, we have built a noninvasive mail inspection system targeting drugs explosives. The is composed two stages; first stage, scattering continuous wave used for selecting that contains concealed powder; second spectrum suspicious measured material identified using database. We evaluated performance limits system.
The effect of terahertz (THz) radiation on deep tissues human body has been considered negligible due to strong absorption by water molecules. However, we observed that the energy THz pulses transmits a millimeter thick in aqueous solution, possibly as shockwave, and demolishes actin filaments. Collapse filament induced irradiation was also living cells under an medium. We confirmed viability cell not affected exposure pulses. potential waves invasive method alter protein structure is demonstrated.
An overview is given on the field of terahertz-frequency electromagnetic waves, their properties and emerging applications. Some widespread sources with advantages drawbacks are presented; an emphasis placed parametric generation that we build use in our research. Several applications then described: imaging techniques based transmission, reflection scattering, results chemical electric imaging, as well linear scanning measurement optical highly-absorbing liquids.
view Abstract Citations (159) References (48) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Correlated Hard X-Ray and Ultraviolet Variability in NGC 5548 Clavel, J. ; Nandra, K. Makino, F. Pounds, A. Reichert, G. Urry, C. M. Wamsteker, W. Peracaula-Bosch, Stewart, Otani, We present the result of a series contemporaneous (within one day) hard X-ray (Ginga) ultraviolet (IUE) observations Seyfert 1 galaxy 5548. Nine these were carried out over period 51 days...
In 1994 May, the BL Lac object PKS 2155-304 was observed continuously for ~10 days with International Ultraviolet Explorer and Extreme 2 ASCA, as well ROSAT ground-based radio, infrared, optical telescopes. The light curves show a well-defined X-ray flare followed by broader, lower amplitude extreme-ultraviolet ~1 day later broad, low-amplitude UV ~2 later. fluxes obtained at three well-separated times preceding week indicate least one previous of comparable or perhaps ongoing stochastic...
We demonstrated terahertz imaging using a direct detector based on niobium superconducting tunnel junctions (STJs). The is composed of linearly distributed placed microstrip line and integrated two wings log-periodic antenna. succeeded nondestructive for an integrated-circuit card dry material the around its sensitivity peak (∼0.66THz). dynamic range was measured to be higher than 4×107 (76dB). Thus, STJ applicable high-sensitivity high-speed various inspection applications.
Terahertz absorption spectra of poly(3-hydroxyalkanoates) with different conformations were measured by using a terahertz time domain spectrometer. Sharp peaks observed in the spectrum crystalline samples. The orientation direction transition dipole moment was investigated polarization spectra. peak at 2.92 THz assigned to vibration helical structure along fiber axis, and 2.49 attributed due hydrogen bonding between helix structures. temperature dependence reflects change distance melting...
The effect of solvent such as ethylene glycol (EG) on the carrier transport in poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS) was studied by combination terahertz (THz) time-domain transmission spectroscopy (0.1–3 THz) and broadband reflectance (4–800 THz). While showed a plasma edge near-infrared, frequency dependence THz conductivity PEDOT/PSS indicated weakly localized behavior. simultaneous fitting both spectra localization-modified Drude model allowed us to...
LiteBIRD [Lite (Light) satellite for the studies of B-mode polarization and Inflation from cosmic background Radiation Detection] is a small to map microwave (CMB) radiation over full sky at large angular scales with unprecedented precision. Cosmological inflation, which leading hypothesis resolve problems in Big Bang theory, predicts that primordial gravitational waves were created during inflationary era. Measurements CMB are known as best probe detect waves. The working group authorized...
This paper reviews our recent spectroscopic study on poly(3-hydroxybutyrate) (PHB) for the terahertz (THz) frequency region. Clear differences are observed between absorption spectra of crystalline and amorphous PHB, indicating that higher order conformation PHB determines THz spectra. The polarization measured a stretched sample directions vibrational transition moments determined. found to have temperature dependences owing which peaks at lower frequencies shift with temperature,...
Abstract As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects macromolecular polymorph, which determines polymer properties and functions. photon energy is quite low compared covalent bond energy; therefore, conformational changes can be induced “softly,” without damaging chemical structures. Here, we irradiate poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization...
Abstract The axion is a hypothetical boson arising from the most natural solution to problem of charge and parity symmetry in strong nuclear force. Moreover, this pseudoscalar emerges as dark matter candidate parameter space extending several decades mass. Dark-photons & Axion-Like particles Interferometer (DALI) proposal search for range that remains under-examined. Currently design prototyping phase, haloscope multilayer Fabry-Pérot interferometer. A proof-of-principle experiment...