An inelastic X-ray scattering spectrometer at LNLS.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Synchrotron Radiation Science

Background:

• Inelastic X-ray scattering (IXS) is a powerful technique for probing electronic excitations.
• High-resolution spectrometers are crucial for resolving low-energy excitations.
• Advancements in synchrotron light sources enable sophisticated experimental setups.

Purpose of the Study:

• To describe a newly developed high-resolution spectrometer for IXS experiments.
• To detail its installation and performance at the National Synchrotron Light Laboratory (LNLS).
• To demonstrate its capability for studying electronic excitations with eV resolution.

Main Methods:

• Utilized synchrotron radiation monochromated to ~6 keV.
• Employed a sagittally focusing Si(111) double-crystal monochromator for sample focusing.
• Implemented Rowland circle geometry with a focusing Si(333) analyzer for energy analysis.
• Varied incident photon energy to obtain energy transfers at a fixed analyzer Bragg angle.

Main Results:

• Achieved a relative energy resolution of approximately 1.5 x 10^-4 at 5.93 keV.
• Successfully measured inelastic X-ray scattering by plasmon excitation in polycrystalline Beryllium (Be).
• Demonstrated the feasibility of eV energy resolution and acceptable counting rates for IXS at LNLS.

Conclusions:

• The new spectrometer is well-suited for IXS studies of electronic excitations.
• The system facilitates research on plasmon and particle-hole excitations at LNLS.
• The achieved performance validates the spectrometer's design for advanced materials research.