REIXS Beamline


Resonant Elastic and Inelastic X-ray Scattering (REIXS) beamline is located at the 10ID-2 straight section. It is a state-of-the-art soft x-ray scattering facility featuring high flux, high resolution, and full polarization control. By means of various photon-in and photon-out techniques under magnetic fields and at different temperatures, the facility is suitable for studying novel and advanced quantum materials, including strongly correlated electron systems, spintronic materials, high Tc superconductor, nano-scale biomaterials, etc.

Beamline Specification and Performance

  • Photon Energy Range: 95 eV – 2000 eV
  • Energy Resolution: 5x10-5 @ 100 eV, 1.3x10-4 @ 1000 eV
  • Flux: 1×1012 @ 100 eV, 5x1011 @ 1000 eV
  • Polarization:
    • Linear polarization in any direction
    • Left / right circular polarization and elliptical polarization
    • Rapid switching of polarization
  • Endstations:
    • Resonant Soft X-ray Scattering (RSXS)
    • Resonant Inelastic X-ray Scattering (RIXS)
    • RSXS Surface Science Facility (offline)
    • RIXS Sample Preparation Annex (offline)
  • Beam Size on the sample:
    • RSXS: 250μm (H) × 150μm (V)
    • RIXS: 50μm (H) × 10μm (V)

The REIXS beamline has the capability to accept light from the two EPUs in the 10ID straight section. The two beams are spatially separated by the chicane magnets in the straight section. The unique double collimating mirror design will compensate for the different source distances and ensure accurate collimation for both beams. All following optical elements are capable of handling two beams; therefore, the two beams have equivalent high performance. In the two beam mode, a rotary chopper is used to select which beam reaches the sample in the endstation. When the two EPUs are generating light with different polarizations, rapid switching of the polarization can be realized.


Source: EPU

The source of the REIXS Beamlilne is an Elliptically Polarizing Undulator (EPU) at the 10ID straight section of the CLS storage ring. The total length of the EPU is 1.6 m with a period of 75 mm. The range of the photon energy is from 80 eV to 2500 eV.


Monochromator: VLS-PGM

The Variable-Line-Spacing Plane Grating Monochromator (VLS-PGM) has three gratings to cover the whole energy range. There are four coatings on the plane mirror, namely Ni, Si, C, and Au. Combination of different coatings and gratings will help optimizing the photon flux and surpress the higher order harmonics.


Beamline Design