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In this study, a combination of X-ray excited optical luminescence (XEOL), time-resolved XEOL (TR-XEOL) and the Hanbury-Brown and Twiss (HB-T) interferometer at the Taiwan Photon Source (TPS) 23A X-ray nanoprobe beamline for exploring quantum materials is demonstrated. On the basis of the excellent spatial resolution rendered using a nano-focused beam, emission distributions of artificial micro-diamonds can be obtained by XEOL maps, and featured emission peaks of a selected local area can be obtained by XEOL spectra. The hybrid bunch mode of the TPS not only provides a sufficiently high peak power density for experiments at each beamline but also permits high-quality temporal domain (~200 ns) measurements for investigating luminescence dynamics. From TR-XEOL measurements, the decay lifetime of micro-diamonds is determined to be approximately 16 ns. Furthermore, the XEOL spectra of artificial micro-diamonds can be investigated by the HB-T interferometer to identify properties of single-photon sources. The unprecedented strategy of combining XEOL, TR-XEOL and the HB-T interferometer at the X-ray nanoprobe beamline will open new avenues with significant characterization abilities for unraveling the emission mechanisms of single-photon sources for quantum materials. [ABSTRACT FROM AUTHOR]

In this study, we used hard X-ray-excited optical luminescence (XEOL) to investigate the emission properties of MgAl 2 O 4 wafers with a crystal orientation of (100), (110), or (111). MgAl 2 O 4 (110) exhibited the lowest XEOL emission intensity because the (110) orientation is thermochemical unstable and therefore unfavorable for generating oxygen vacancies. By fitting XEOL spectra, we identified 13 and 6 clear emission peaks corresponding to the color centers in MgAl 2 O 4 wafers and the 2E g →4A 2g radiative transition of Cr ion impurities, respectively. Using an X-ray nanoprobe, we obtained an X-ray fluorescence spectroscopy (XRF) map of the elemental distribution of Cr with 100 nm spatial resolution. X-ray absorption spectroscopy (XAS) revealed that the valence state of the Cr ion impurities was Cr3+. We thus also clearly demonstrate the advantages of combining XEOL, XRF, and XAS in the X-ray nanoprobe beamline by obtaining emission spectra using XEOL and using XRF and XAS to analyze elemental distributions and valence states to further elucidate the emissions of samples. • The emission properties of the color centers in MgAl 2 O 4 wafers has been investigated by XEOL. • We identified 13 clear emission peaks corresponding to the color centers in MgAl 2 O 4 wafers. • X-ray absorption spectroscopy (XAS) revealed that the valence state of the Cr ion impurities was Cr3+. [ABSTRACT FROM AUTHOR]

We review the main developments and first commissioning experiments at the CARNAÚBA X-ray nanoprobe beamline, recently installed at the brand-new Sirius 4th-generation synchrotron radiation source at the Brazilian Synchrotron Light Laboratory (LNLS). The paper briefly discusses the X-ray nanoprobe instrument, emphasizing the first deployed experimental station TARUMÃ, and showcases preliminary results in a broad range of areas that benefit from diverse sample environments. Research domains like photovoltaics, photonics, electrocatalysis, geoscience, and agriculture are investigated from the viewpoint of chemistry, atomic structure, morphology, and redox dynamics phenomena covered by the beamline techniques. Finally, future capabilities are presented based on a new instrument under development. • The CARNAUBA X-ray nanoprobe beamline has been commissioned and it is open to the scientific community. • The first deployed station, named TARUMÃ, has been commissioned and reached design parameters. • The beamline has delivered preliminary science outcomes. [ABSTRACT FROM AUTHOR]

We describe the first use of a novel photoresist-free X-ray nanopatterning technique to fabricate an electronic device. We have produced a proof-of-concept device consisting of a few Josephson junctions by irradiating microcrystals of the Bi2Sr2CaCu2O8+δ (Bi-2212) superconducting oxide with a 17.6 keV synchrotron nanobeam. Fully functional devices have been obtained by locally turning the material into a nonsuperconducting state by means of hard X-ray exposure. Nano-XRD patterns reveal that the crystallinity is substantially preserved in the irradiated areas that there is no evidence of macroscopic crystal disruption. Indications are that O ions have been removed from the crystals, which could make this technique interesting also for other oxide materials. Direct-write X-ray nanopatterning represents a promising fabrication method exploiting material/material rather than vacuum/material interfaces, with the potential for nanometric resolution, improved mechanical stability, enhanced depth of patterning, and absence of chemical contamination with respect to traditional lithographic techniques. [ABSTRACT FROM AUTHOR]

Within the framework of the ESRF Phase I Upgrade Programme, a new state-of-the-art synchrotron beamline ID16B has been recently developed for hard X-ray nano-analysis. The construction of ID16B was driven by research areas with major scientific and societal impact such as nanotechnology, earth and environmental sciences, and bio-medical research. Based on a canted undulator source, this long beamline provides hard X-ray nanobeams optimized mainly for spectroscopic applications, including the combination of X-ray fluorescence, X-ray diffraction, X-ray excited optical luminescence, X-ray absorption spectroscopy and 2D/3D X-ray imaging techniques. Its end-station re-uses part of the apparatus of the earlier ID22 beamline, while improving and enlarging the spectroscopic capabilities: for example, the experimental arrangement offers improved lateral spatial resolution (∼50 nm), a larger and more flexible capability for in situ experiments, and monochromatic nanobeams tunable over a wider energy range which now includes the hard X-ray regime (5-70 keV). This paper describes the characteristics of this new facility, short-term technical developments and the first scientific results. [ABSTRACT FROM AUTHOR]

The Hard X-ray Nanoprobe Beamline (or Nanoprobe Beamline) is an X-ray microscopy facility incorporating diffraction, fluorescence and full-field imaging capabilities designed and operated by the Center for Nanoscale Materials and the Advanced Photon Source at Sector 26 of the Advanced Photon Source at Argonne National Laboratory. This facility was constructed to probe the nanoscale structure of biological, environmental and material sciences samples. The beamline provides intense focused X-rays to the Hard X-ray Nanoprobe (or Nanoprobe) which incorporates Fresnel zone plate optics and a precision laser sensing and control system. The beamline operates over X-ray energies from 3 to 30 keV, enabling studies of most elements in the periodic table, with a particular emphasis on imaging transition metals. [ABSTRACT FROM AUTHOR]

• Homogeneous Sn distribution in GeSn micro-disks with very high Sn concentration. • SiGeSn buffer allows perfect GeSn micro-disks by providing better etching control. • First X-ray absorption spectroscopy on GeSn micro-disks with nanometre resolution. • Step-graded buffer avoids Sn segregation in GeSn thick layers with up to 16% of Sn. • Growth directly on Ge buffer generates Sn precipitation in high Sn-content layers. High Sn-content Ge 1-x Sn x alloys are excellent candidates for the fabrication of electronic and optoelectronic monolithically integrated devices on CMOS platforms. The fabrication of high performance devices requires high quality GeSn layers free of Sn precipitates. This work reports on the characterization of GeSn layers and micro-disk lasers with Sn concentrations ranging from 6 to 16% using synchrotron nano X-ray fluorescence mapping and nano X-ray absorption spectroscopy techniques. We demonstrate that the Sn precipitation observed in thick GeSn layers grown directly on Ge buffers can be fully suppressed, for Sn concentrations as high as 16%, with Ge 1-x Sn x step-graded buffers. The combination of optimal micro-disk fabrication parameters and full suppression of Sn precipitation can explain the superior lasing performance obtained in micro-disk lasers fabricated using such stacks. [ABSTRACT FROM AUTHOR]