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

Research output: Contribution to journalArticle


Over the past decade, the advances in grating-based soft X-ray spectrometers have revolutionized
the soft X-ray spectroscopies in materials research. However, these novel spectrometers are mostly
dedicated designs, which cannot be easily adopted for applications with diverging demands. Here we
present a versatile spectrometer design concept based on the Hettrick-Underwood optical scheme that
uses modular mechanical components. The spectrometer’s optics chamber can be used with gratings
operated 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 resolving
power 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 with
slightly different design goals and optical parameters in this paper. We show that the spectrometer with
high throughput and large energy window is particularly useful for studying the sustainable energy
materials. We demonstrate that the extensive resonant inelastic X-ray scattering (RIXS) map of battery
cathode 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 the
elemental absorption edges to determine various spectral features like the localized dd excitations and
non-resonant fluorescence emissions, these features can be easily identified in the RIXS maps. Studying
such RIXS maps could reveal novel transition metal redox in battery compounds that are sometimes
hard to be unambiguously identified in X-ray absorption and emission spectra. We propose that this
modular spectrometer design can serve as the platform for further customization to meet specific
scientific demands.


  • Yi-De Chuang
  • Yu-Cheng Shao
  • Alejandro Cruz
  • Kelly Hanzel
  • Adam Brown
  • Alex Frano
  • Ruimin Qiao
  • Brain Smith
  • Edward Domning
  • L Andrew Wray
  • Wei-Sheng Lee
  • Zhi-Xun Shen
  • Thomas P. Devereaux
  • Jaw-Wen Chiou
  • Way-Faung Pong
  • Valeriy V. Yashchuk
  • Eric Gullikson
  • Ruben Reininger
  • Wanli Yang
  • Jinghua Guo
  • Robert Duarte
  • Zahid Hussain
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Atom and Molecular Physics and Optics
Original languageEnglish
Article number013110
JournalReview of Scientific Instruments
Issue number1
Publication statusPublished - 2017 Jan 27
Publication categoryResearch