The meV XUV-RIXS facility at UE112-PGM1 of BESSY II

Abstract

Resonant inelastic X-ray scattering in the XUV-regime has been implemented at BESSY II, pushing for a few-meV bandwidth in inelastic X-ray scattering at transition metal M-edges, rare earth N-edges and the K-edges of light elements up to carbon with full polarization control. The new dedicated low-energy beamline UE112-PGM1 has been designed to provide 1 µm vertical and 20 µm horizontal beam dimensions that serve together with sub-micrometre solid-state sample positioning as the source point for a high-resolution plane grating spectrometer and a high-transmission Rowland spectrometer for rapid overview spectra. The design and commissioning results of the beamline and high-resolution spectrometer are presented. Helium autoionization spectra demonstrate a resolving power of the beamline better than 10 000 at 64 eV with a 300 lines mm−1 grating while the measured resolving power of the spectrometer in the relevant energy range is 3000 to 6000.

Role of La 5p in Bulk and Quantum-Confined Solids Probed by the La 5p54f1 3D1 Excitonic Final State of Resonant Inelastic X-ray Scattering

“…Figure a shows the experimental RIXS data of the La 5p 5 4f 1 3 D 1 and 3 D 2 final states of lanthanum metal, La 2 O 3 , SrLaAlO 4 , LaAlO 3 , LaPO 4 :Ce,Tb, and LaF 3 measured with unprecedented subnatural line width spectral resolution of 45–60 meV at the meV-RIXS experimental station of BESSY II . Gradual shift of the leading edge and different broadening are observed.…”

“…In a nutshell, all levels are of mixed nature except for the energetically lowest 3 D 1 state. For this reason, we base all further analysis on the La 5p 5 4f 1 3 D 1 RIXS final state shown in Figure 2e, since the high spectral resolution 52 allows us to distinguish the 3 D 1 and 3 D 2 contributions, which were inseparable in previous work. 42,57 Figure 3.…”

“…The X-ray absorption spectroscopy (XAS) and RIXS experiments were performed at BESSY-II (Helmholtz-Zentrum Berlin) at beamline U49 50 with the SolidFlexRIXS end station 51 for the overview RIXS spectra and at the UE112-PGM1 with the meV-RIXS permanent end station 52 for the high-resolution RIXS spectra. The measurements were carried out at room temperature at 10 −8 mbar pressure with a linearly polarized beam.…”

Orbital-overlap-driven hybridization in 3d-transition metal perovskite oxides LaMO3 (M = Ti-Ni) and La2CuO4

“…The N 4,5 -edges RIXS experiments were performed at BESSY II (Helmholtz-Zentrum Berlin) at the beamline UE112-PGM1 with the meV-RIXS spectrometer 66 and beamline U49 67 with the SolidFlexRIXS end station 68 . All thin films were grown on SrTiO 3 (STO) substrate if not explicitly noted.…”