In recent years, with the vigorous development of the fourth-generation synchrotron radiation light sources with high brightness and low emittance, the domestic demand for high energy resolution X-ray spectroscopy instruments has become increasingly urgent. As the core energy detection unit of the Rowland circle spectrometer, the spherical crystal analyzer has the dual functions of X-ray focusing and energy resolution. It is one of the indispensable optical components for "photon-hungry" experiments. Developing high-quality spherical crystals analyzer with energy resolutions of tens of milli-eV is a very challenging problem, and it is also a key technology that urgently needs to be overcome in the field of domestic synchrotron radiation light sources.
The speaker reported on the latest progress in independently developing analyzer crystals for the High Energy Synchrotron Radiation Source (HEPS). The potential applications of analyzer crystals in advanced X-ray spectroscopy and inelastic X-ray scattering (IXS) are introduced. Relying on the construction of high-energy resolution spectroscopy beamline, the project team has successively developed a spherical bend analyzer crystal with an energy resolution of 1eV, and a strip stress-release analyzer crystal with an energy resolution of 0.5eV [1]. In particular, we have made the spherically curved “diced-flat” crystal with energy resolution better than 50meV. These optical components can be widely used in advanced X-ray spectroscopy experimental methods, such as high-resolution fluorescence detection X-ray absorption spectroscopy (HERFD-XANES), resonant/non-resonant X-ray emission spectroscopy ((R)XES) [2], etc. etc.; In addition, it can also be applied to light-in/light-out inelastic X-ray scattering experimental techniques, such as X-ray Raman scattering (XRS) to study high-pressure chemical bonds and hydride superconductivity, and study magnons and low-energy element-excited resonant inelastic X-ray scattering (RIXS) and so on. At the same time, the development of ultra-high energy resolution crystals will face greater technical challenges. The reporter reported on possible paths to apply new materials and new technologies to break through the energy resolution of 1-10meV in the hard X-ray band, which will have a great impact on domestic meV-IXS. The establishment of methodology, high-pressure physics research, and detection of phonons and their dispersion relationships are crucial.
 

Analyzer Crysal,Inelastic X ray Scattering