We report on the development of a high-resolution and highly efficient beamline for soft X-ray resonant inelastic X-ray scattering (RIXS) located at the Taiwan Photon Source. This beamline adopts an optical design that uses an active grating monochromator (AGM) and an active grating spectrometer (AGS) to implement the energy compensation principle of grating dispersion. Active gratings are utilized to diminish defocus, coma and higher-order aberrations, as well as to decrease the slope errors caused by thermal deformation and optical polishing. The AGS is mounted on a rotatable granite platform to enable momentum-resolved RIXS measurements with scattering angles over a wide range. Several high-precision instruments developed in-house for this beamline are described briefly. The best energy resolution obtained from this AGM–AGS beamline was 12.4 meV at 530 eV, achieving a resolving power of 4.2 × 104, while the bandwidth of the incident soft X-rays was kept at 0.5 eV. To demonstrate the scientific impact of high-resolution RIXS, we present an example of momentum-resolved RIXS measurements on a high-temperature superconducting cuprate, i.e. La2–x Sr x CuO4. The measurements reveal the A1g buckling phonons in superconducting cuprates, opening a new opportunity to investigate the coupling between these phonons and charge-density waves.

Original and Ar-implanted Ti-Zr-V non-evaporable getter (NEG) films were characterized using scanning electron microscope, X-ray diffractometer, electron spectroscopy for chemical analysis, and transmission electron microscopy. Similar properties and results were observed in the surface morphology, the composition, and the crystalline structure for original and implanted Ti-Zr-V films. However, the thermal activation temperature were increased for implanted films. The analysis of implanted Ti-Zr-V films revealed that defects formed in the upper layers of the films can trap diffused gaseous atoms from the surface into the Ti-Zr-V films. Therefore, the thermal activation reaction of Ti-Zr-V films would be affected due to implantation-induced defects in the films. We show directly that the thermal activation reaction of Ti-Zr-V films are changed by the existence of defects in the getter films.

The Ti-Zr-V non-evaporable getter (NEG) films were grown on Aluminum (Al) alloy and CuCrZr alloy, which can be used to fabricate the vacuum chambers in the ultra-high vacuum status. The Al alloy and CuCrZr alloy samples with different surface roughness were prepared by the different manufacturing methods. We studied whether the behavior and the microstructure of the Ti-Zr-V getter films are influence by the surface roughness of the substrate. The surface morphologies of Ti-Zr-V NEG films appear distinct and the growth of the films follows the nature of the substrate surface. The Ti-Zr-V films have nanocrystalline structures and the grain sizes of the films become slightly larger with increasing the surface smoothness. In addition, it was found that the reduction of the Ti-Zr-V NEG films to the metallic state was affected by presence of surface defects on the films. The surface defects should result from the existence of micro-pores, pockmarks, and micro-cracks on the original substrate, which produced from the manufacturing process.

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