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To achieve diffraction-limited focal spot size is a goal for next-generation synchrotrons. Mirrors are increasingly important for X-ray focusing optics following recent advances in mirror fabricati...

The project of transmission x-ray microscope (TXM) with tender x-ray is undergoing as an extension project of the soft x-ray tomography (SXT) endstation at Taiwan Photon Source (TPS). This TXM is aimed for energy from 1.5 keV to 2.4 keV and with phase contrast with the x-ray energy of 2.4 keV. As the extension of current SXT project, the beamline will be equipped with a variable line spacing (VLS) grating with the multi-layer coating which will be optimized for 2.4 keV. This TXM will be zoneplate based with a phase ring and capillary condenser. In order to match the field of view and numerical aperture (NA) of zoneplate with the emittance of the source in vertical direction, some compromise should be made. To match the low emittance of vertical direction, the NA of zoneplate should be lower and vertical of the secondary source should be larger. This will lower spatial resolution and energy resolution. The targeting resolution of this TXM for phase contrast will be 50nm and FOV is 20 μm. For the detector, which is currently design with a scintillator with a CCD detector. For the future, the direct detector for small pixel and high signal to noise ratio can be obtained. The other components of TXM, such as stages, cryo system, which can be shared with current SXT system which works under the energy of the water window region. This endstation for tender X-ray will be commission in 2020. The detailed design and current progress will be discussed in this presentation.

Polarization-dependent hard X-ray excited optical luminescence (XEOL) was used to study not only the optical properties but also the crystallographic orientations of a non-polar a-plane ZnO wafer. In addition to a positive-edge jump and extra oscillations in the near-band-edge (NBE) XEOL yield, we observed a blue shift of the NBE emission peak that follows the polarization-dependent X-ray absorption near-edge structure (XANES) as the X-ray energy is tuned across the Zn K-edge. This NBE blue shift is caused by the larger X-ray absorption, generating higher free carriers to reduce the exciton-LO phonon coupling, which causes a decrease in the exciton activation energy. The extra oscillations in XANES and XEOL as the polarization is set parallel to the c-axis is attributed to simultaneous excitations of the Zn 4p - O 2pπ -bond along the c-axis and the bilayer σ-bond, whereas only the σ-bond is excited when the polarization is perpendicular to the c-axis. The polarization-dependent XEOL spectra can be used to determine the crystallographic orientations.

The diffraction-limited Montel mirrors, equipped at the X-ray Nanoprobe (XNP) at Taiwan Photon Source (TPS), provide a 40 nm focal spot and working distance 55 mm under the total beamline length of 69 m. The underneath holder supporting for the Montel mirrors is a 12 axes flexure based manipulators in which 10 out of the 12 axes are motorized. To monitor the position and stability of individual holder motion, a monitoring system consisted of three optical encoders and three- axes laser interferometers for angle movement is implemented. The gap width between the two mirrors and their orthogonality can be adjusted by a tilting sensor and a high magnification optical microscope. The focusing properties, phase and amplitude, after the Montel mirrors will be investigated by means of coherent Ptychography, as well as by zone plate imaging. An SEM in close cooperation with laser interferometers is equipped to precisely position the samples and conduct the on-the-fly scan. A high speed FPGA based circuit is developed to address signal from XRF, XAS, XEOL and XRD. Data is in tag with position and time information and been processed by computers to allow 5nm precision stage scanning free from mechanical feedback. The XNP at TPS is under commissioning since February 2017. The commissioning result, particularly the performance of the Montel mirrors will be reported in this presentation.

The hard X-ray nanoprobe facility at Taiwan Photon Source (TPS) provides versatile X-ray analysis techniques, with tens of nanometer resolution, including XRF, XAS, XEOL, projection microscope, CDI, etc. Resulting from the large numerical aperture obtained by utilizing Montel KB mirrors, the beamline with a moderate length 75 meters can conduct similar performance with those beamlines longer than 100 meters. The two silica-made Montel mirrors are 45 degree cut and placed in a V-shape to eliminate the gap loss and the deformation caused by gravity. The slope error of the KB mirror pair is less than 0.04 µrad accomplished by elastic emission machining (EEM) method. For the beamline, a horizontal DCM and two-stage focusing in horizontal direction is applied. For the endstation, a combination of SEM for quickly positioning the sample, a fly scanning system with laser interferometers, a precise temperature control system, and a load lock transfer system will be implemented. In this presentation, the design and...

The hard X-ray nanoprobe facility at Taiwan Photon Source (TPS) provides multimodal X-ray detections, including XRF, XAS, XEOL, projection microscope, CDI, etc. Resulting from the large numerical aperture obtained by utilizing nested Montel mirrors, the beamline with a moderate length 75 meters can conduct similar performance with those beamlines longer than 100 meters. The mirrors are symmetrically placed with a 45 degrees cut. The beamline optics is thus designed to take the advantage of the symmetry of mirrors such that a round focal spot is accomplished. The size and the divergence of the focus spot are simulated around 40 nm and 6.29 mrad, respectively. The whole facility including the beamline and the stations will be operated under vacuum to preserve the photon coherence as well as to prevent the system from unnecessary environmental interference. A SEM in close cooperation with laser interferometers is equipped to precisely locate the position of the sample. This endstation is scheduled to be commissioned in the fall of 2016.

The hard X-ray nanoprobe at Taiwan Photon Source (TPS) makes use of the large numerical aperture obtained by nested Montel mirrors. To fully uptake the focusing power and flux, these mirrors requires the surface slope error no less than 0.05 μrad and are symmetrically placed with a 45 degrees cut for perfect surface matching. The beamline optics is designed to take the advantage of the symmetry of mirrors such that a round focal spot is accomplished. The final size of the focus spot are simulated below 40 nm at 9-15 keV. The whole facility including the beamline and the stations will be operated under vacuum to preserve photon coherence as well as to prevent the system from unnecessary environmental interference. The station equips with multimodal x-ray probes, including XRF, XAS, XEOL, projection microscope, CDI, etc. A SEM in close cooperation with laser interferometers is equipped to precisely locate the position of the sample. The beamline and the station are scheduled to be in commissioning phase in 2016.

A positive myocardial inotropic effect achieved using HNO/NO(-) , compared with NO⋅, triggered attempts to explore novel nitroxyl donors for use in clinical applications in vascular and myocardial pharmacology. To develop M-NO complexes for nitroxyl chemistry and biology, modulation of direct nitroxyl-transfer reactivity of dinitrosyl iron complexes (DNICs) is investigated in this study using a Fe(III) -porphyrin complex and proteins as a specific probe. Stable dinuclear {Fe(NO)2 }(9) DNIC [Fe(μ-(Me) Pyr)(NO)2 ]2 was discovered as a potent nitroxyl donor for nitroxylation of Fe(III) -heme centers through an associative mechanism. Beyond the efficient nitroxyl transfer, transformation of DNICs into a chemical biology probe for nitroxyl and for pharmaceutical applications demands further efforts using in vitro/in vivo studies.

The temperature-dependent hard X-ray excited optical luminescence (XEOL) spectroscopy was used to study the optical properties of O and Zn polarity of a c-plane single crystal ZnO wafer. By analyzing the XEOL and XRD, we found an unprecedented blue shift of the free exciton transition with increasing the excited carrier density as tuning the X-ray energy across the Zn K-edge, and the O-polar face possesses better crystal structure than the Zn-polar one. This spectral blue shift is attributed to the Coulomb screening of the spontaneous polarization by the excited free carriers that result in decreasing the exciton-phonon Frohlich interaction to reduce exciton binding energy.