High-resolution RIXS of solids in the XUV regime at UE112-PGM-1
The meV-RIXS station is dedicated to the element-selective investigation of solid systems by high-resolution RIXS of low energy excitations in the XUV regime, with emphasis on transition metal M-edges, rare earth N-edges and K-edges of light elements. The station includes an additional complementary lower-resolution / higher-energy range RIXS spectrometer for overview spectra suited for preliminary investigations.Selected Applications:
- dd and spin-flip excitations in transition metal oxides, e.g. NiO at the Ni M2,3 edges
- multiplet excitations in rare-earth compounds, e.g. chemical shift and bandgap determination of Lanthanum compounds via RIXS at the La N4,5 edges
- Lattice vibrations and electron phonon coupling using K-edges of low-Z elements from Be to B
|Energy range||8 - 690 eV; for extreme values (<50 eV or >400 eV) contact the beamline crew|
|Energy resolution||30,000 (20-150eV)|
> 20,000 (150-350eV) (standard grating)
|Flux||> 2x1012 ph/s (20-280eV)|
ca. 4x1013 ph/s (50-150eV) (standard grating)
|Focus size (hor. x vert.)||optimum: ca. 0.001 x 0.02 mm (V x H, FWHM, inside sample chamber)|
|Phone||+49 30 8062 14836|
|Temperature range||Base temperature of liquid N2 and He, full temperature control in testing|
|Pressure range||UHV range (<10-9 mbar)|
|Detector||Microchannel plate + delay line detector|
|Sample holder compatibility||Custom-made sample holder for solid samples of dimensions 10x10x5 mm or smaller|
The meV RIXS plane grating spectrometer consists of two parabolical mirrors with a plane grating in between. The first mirror collects and collimates the radiation from the 1x4 μm2 beamline microfocus on the sample onto the grating while the second mirror focusses the diffracted light onto the detector. The spectrometer houses two laminar grating structures on a common substrate: 1050 l/mm for high transmission and 4200 l/mm for high resolution. The photons are detected by a PHOTONIS multi channel pate (MCP) stack in combination with a RoentDek delay line detector DLD-120. The MCP channel diameter is 25 um and the top MCP is coated with CsI to improve the quantum efficiency of the detector.
The samples are mounted in the solid state experimental chamber directly to a Janis ST-500 Microscopy Cryostate which allows for a maximum stability for the sample position. To avoid mechanical instabilities in sample positioning, no sample translation stage is installed, but the whole vacuum chamber can be positioned by a 3-axis Huber table vertically and in the horizontal plane. Rotation of the sample around the vertical axis is achieved via a rotation of the microscope cryostate.
The meV RIXS spectrometer is permanently situated at the UE112-PGM beamline while the solid state experimental chamber.
For details and current status of the experimental station contact the station scientist.