chemRIXS/qRIXS Experimental Methods

NEH 2.2 will host a wide range of experimental methods with flexible instrumentation. The high repetition rate of LCLS-II will provide outstanding signal-to-noise ratio. All of these methods will be compatible with ultrafast time resolved pump-probe studies.

chemRIXS

• X-ray Absorption Spectroscopy (XAS): XAS will be carried out either directly in transmission, in Total Fluorescence Yield mode via in-vacuum single-photon sensitive detectors, or in Partial Fluorescence Yield mode via wavelength-dispersing grating spectrometer.
• X-ray Emission Spectroscopy (XES): Resonant or non-resonant XES will be carried out with the use of a grating spectrometer.

qRIXS

• Resonant Inelastic X-ray Scattering (RIXS): RIXS in condensed matter systems will be used to extract the energy-momentum dispersion of elementary excitations of lattice, electronic, spin and orbital nature.  The measurement is made possible with the use of a 6 meter long x-ray emission spectrometer, continuously covering a range of over 100 deg in the scattering plane.
• X-ray Absorption Spectroscopy (XAS): XAS measurements will be made in Total Fluorescence Yield mode with the use of single photon sensitive point detectors, such as avalanche photodiodes (APD) or microchannel plate detectors (MCP), shielded from stray optical light.
• Resonant Elastic X-ray Scattering (REXS): Bragg and/or superstructure reflections can be measured with the help of APDs in the horizontal plane.  Accurate sample and detector motion will be facilitated by the use of an in-vacuum diffractometer.
• X-ray Photon Correlation Spectroscopy (XPCS): Intrinsic fluctuations in the ground state of correlated systems can be traced by monitoring the speckle correlation at different time scales.  This will be achieved by placing an area detector at a distance of up to 6 m away from the sample in the horizontal plane.