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Hiroshi Sugiyama

Publications and source records attributed to Hiroshi Sugiyama.

4 recordsLinked to original sources

Recent application studies of an INTPIX4NA SOIPIX detector-based X-ray camera using an SiTCP-XG 10GbE-based high-speed readout system at KEK facilities

The Silicon-On-Insulator PIXel (SOIPIX) detector is a unique monolithic structure imaging device currently being developed by the SOIPIX group, led by the High Energy Accelerator Research Organization (KEK). Our detector team at the KEK Photon Factory (PF) has developed an X-ray camera based on the INTPIX4NA SOIPIX detector. This detector provides a sensitive area of 14.1 $\times$ 8.7 $\mathrm{mm^2}$, with 425,984 pixels arranged in an 832-column $\times$ 512-row matrix and a pixel size of 17 $\times$ 17 $\mathrm{μm^{2}}$, and offers high spatial resolution and excellent sensitivity under low-intensity X-ray conditions. The readout system used in the X-ray camera is developed at the PF. It is equipped with SiTCP-XG, a 10 Gb Ethernet network controller implemented on a field-programmable gate array, enabling high-frame-rate imaging at several hundred hertz. We are currently investigating the applicability of this X-ray camera in several experiments at KEK. Herein, we report three recent application studies: (1) X-ray zooming microscope optics using two Fresnel zone plates at PF AR-NE1A; (2) phase-contrast X-ray imaging system using a two-crystal X-ray interferometer at PF BL-14C; and (3) nondestructive lithium detection in Li-ion battery electrode materials using muonic X-rays at J-PARC MLF Muon D2.

physics.ins-det↗

Development of a new phase-retrieval algorithm from a single-shot image for X-ray schlieren microscopy

In this paper, a new phase-retrieval algorithm from an X-ray schlieren image is proposed. The schlieren method allows phase-contrast imaging with an objective lens and a knife-edge filter placed at the back focal plane of the objective. This method finds a wide range of applications in the visible-light region for transparent specimen visualization. The schlieren contrast does not directly correspond to the phase shift. However, the phase map can be reconstructed from a single-shot schlieren image of a transparent and weak-phase object using the filtered Fourier transform method. A proof-of-principle experiment was performed in the hard-X-ray region at the AR-NE1A beamline of the Photon Factory facility at the High Energy Accelerator Research Organization (KEK).

physics.ins-det↗

A light-driven three-dimensional plasmonic nanosystem that translates molecular motion into reversible chiroptical function

Nature has developed striking light-powered proteins such as bacteriorhodopsin, which can convert light energy into conformational changes for biological functions. Such natural machines are a great source of inspiration for creation of their synthetic analogues. However, synthetic molecular machines typically operate at the nanometre scale or below. Translating controlled operation of individual molecular machines to a larger dimension, for example, to 10-100 nm, which features many practical applications, is highly important but remains challenging. Here we demonstrate a light-driven plasmonic nanosystem that can amplify the molecular motion of azobenzene through the host nanostructure and consequently translate it into reversible chiroptical function with large amplitude modulation. Light is exploited as both energy source and information probe. Our plasmonic nanosystem bears unique features of optical addressability, reversibility and modulability, which are crucial for developing all-optical molecular devices with desired functionalities.

physics.optics↗

Polaronic behavior of photoelectron spectra of Fe3O4 revealed by both hard X-ray and extremely low energy photons

Hard X-ray and extremely low energy bulk-sensitive photoelectron spectroscopy has been performed in the temperature range of 100-330 K for Fe3O4. In the high temperature phase just above the Verwey transition, the intensity at the Fermi level (EF) is still negligible, but it increases gradually with further increasing the temperature (250 K, 330 K) in consistence with the temperature dependence of the conductivity. The spectral behaviors near EF with temperature are well explained by the model, which takes the polaron effect into account.

cond-mat.str-el↗