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We have developed a dynamic simulation method to analyze TES dynamics. This simulation code is based on heat diffusion and Maxwell’s equations. With this simulation, we can calculate transition temperatures and can map current flow in the devices. We can also reproduce signal waveforms. We apply this method to our new TESs. Our new structures are a combination of a TES (e.g., Ir) and a serially connected radiation absorber (e.g., Au). In this design, Joule heating in the TES and radiation absorber stabilizes the absorber temperature through a negative feedback process. What is more, with this new design scheme, we can tune TES parameters such as residual resistivity ratio (RRR), transition width, and normal electrical resistance. As a trial, we have fabricated two iridium TESs with 150um×150um×390nm gold absorbers mounted on a common silicon nitride membrane. Sizes of the TESs are 25um×25um×100nm, and 25um×50um×100nm respectively. They are parallel voltage biased to one readout circuit. The simulation sho...

A monochromator stabilization system with a semi‐automatic tuning procedure has been developed. The system comprises an X‐ray beam position/intensity monitor, a control electronics unit, a computer program that operates on a personal computer or workstation, a piezo translator attached to the first crystal of a double crystal monochromator, and a phase‐sensitive detector as an optional component. The system suppressed the fluctuations of the photon beam intensity and the beam position by ∼0.1% and ∼1 μm, respectively, at the sample locations in the beamlines of SPring‐8 with a frequency of less than 10 Hz. The system with the phase‐sensitive detector holds the peak of the rocking curve of the double crystal monochromator, which is effective in reducing the time required to perform the energy scan measurement.

State‐sensitive XAFS was enabled combined with high‐energy‐resolution (ΔE = 0.3 eV@5.5 keV) X‐ray fluorescence spectrometry and applied to Au sites of An/TiO2 and Sn promoter sites of Pt‐Sn/SiO2. Each state of interfacial Au sites located on Ti/O atoms and negatively/positively charged Aun clusters was discriminated. Feasibility of more direct information of on‐site catalysis via frontier orbital‐sensitive XAFS was demonstrated.

Indium K‐edge EXAFS measurements were carried out to study local structures around In atoms in InxGa1−xN multi‐quantum‐well (MQW) structures of 10 periods with In0.2Ga0.8N (2.5 nm) and In0.05Ga0.95N (7.5 nm). We found the following: (1) Debye‐Waller factors for In‐In and In‐Ga atomic pairs in MQW are smaller than those in single QW (SQW) InxGa1−xN. (2) The differences in the interatomic distances of In‐In and In‐Ga between the horizontal and vertical direction are small. These results indicate that the strain in the InxGa1−xN layer is reduced in MQW in comparison to SQW. (3) In atoms are randomly distributed in both the horizontal and vertical directions of the sample.

We designed and fabricated new diamond detector head for an X‐ray beam position monitor (XBPM). This monitor operates in photoconductive mode, and is shaped into a blade in order to reduce heat load. A pair of aluminum electrodes is formed on both sides of the diamond blade. The profile of the detection efficiency inside the diamond detector head was measured. The signal current is generated only between the pair of electrodes. The bias voltage dependence of signal current along a section of the detector head is also measured. The results show that the detector head operates in photoconductive mode. We demonstrated that this detector head is feasible for the XBPM.

The SPring‐8 bending magnet beamline BL38B1 is designed for R&D of optics, detectors, experiments for XAFS and protein X‐ray crystallography (PX). This beamline has a multi‐purpose hutch for two experimental stations of XAFS and PX, and removable optical benches used for R&D of detectors and instruments. The design and the performance of the beamline are presented.

X-ray fluorescence holography is a technique which can record the amplitude and phase of X-rays scattered by atoms and directly provide three dimensional atomic image of an environment around the atoms, emitting the fluorescence. We used this method to image the local atomic environment of Zn atoms doped in a GaAs wafer using synchrotron radiation and a multi-element solid state detector. The first two neighbor atomic image on (001) plane were successfully obtained, revealing that the Zn atoms occupied substitutional site.