Modular soft x-ray spectrometer for applications in energy sciences and quantum materials

• Over the past decade, the advances in grating-based soft X-ray spectrometers have revolutionizedthe soft X-ray spectroscopies in materials research. However, these novel spectrometers are mostlydedicated designs, which cannot be easily adopted for applications with diverging demands. Here wepresent a versatile spectrometer design concept based on the Hettrick-Underwood optical scheme thatuses modular mechanical components. The spectrometer’s optics chamber can be used with gratingsoperated in either inside or outside orders, and the detector assembly can be reconfigured accordingly.The spectrometer can be designed to have high spectral resolution, exceeding 10 000 resolvingpower when using small source (∼1 µm) and detector pixels (∼5 µm) with high line density gratings(∼3000 lines/mm), or high throughput at moderate resolution. We report two such spectrometers withslightly different design goals and optical parameters in this paper. We show that the spectrometer withhigh throughput and large energy window is particularly useful for studying the sustainable energymaterials. We demonstrate that the extensive resonant inelastic X-ray scattering (RIXS) map of batterycathode material LiNi1/3Co1/3Mn1/3O2 can be produced in few hours using such a spectrometer.Unlike analyzing only a handful of RIXS spectra taken at selected excitation photon energies across theelemental absorption edges to determine various spectral features like the localized dd excitations andnon-resonant fluorescence emissions, these features can be easily identified in the RIXS maps. Studyingsuch RIXS maps could reveal novel transition metal redox in battery compounds that are sometimeshard to be unambiguously identified in X-ray absorption and emission spectra. We propose that thismodular spectrometer design can serve as the platform for further customization to meet specificscientific demands.

Ämnesord

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)