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DOE OSTI · 1840017

IRIXS Spectrograph: an ultra high-resolution spectrometer for tender RIXS

Bertinshaw, Joel·Mayer, Simon·Dill, Frank-Uwe·Suzuki, Hakuto·Leupold, Olaf·Jafari, Atefeh·Sergueev, Ilya·Spiwek, Manfred·Said, Ayman·Kasman, Elina·Huang, Xianrong·Keimer, Bernhard·Gretarsson, Hlynur
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Abstract

The IRIXS Spectrograph represents a new design of an ultra-high-resolution resonant inelastic X-ray scattering (RIXS) spectrometer that operates at the Ru L 3 -edge (2840 eV). First proposed in the field of hard X-rays by Shvyd'ko [(2015), Phys. Rev. A, 91, 053817], the X-ray spectrograph uses a combination of laterally graded multilayer mirrors and collimating/dispersing Ge(111) crystals optics in a novel spectral imaging approach to overcome the energy resolution limitation of a traditional Rowland-type spectrometer [Gretarsson et al. (2020), J. Synchrotron Rad. 27, 538–544]. In combination with a dispersionless nested four-bounce high-resolution monochromator design that utilizes Si(111) and Al 2 O 3 (110) crystals, an overall energy resolution better than 35 meV full width at half-maximum has been achieved at the Ru L 3 -edge, in excellent agreement with ray-tracing simulations.

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Bertinshaw, Joel, Mayer, Simon, Dill, Frank-Uwe, Suzuki, Hakuto, Leupold, Olaf, Jafari, Atefeh, Sergueev, Ilya, Spiwek, Manfred, Said, Ayman, Kasman, Elina, Huang, Xianrong, Keimer, Bernhard, Gretarsson, Hlynur. 2021-05-27. IRIXS Spectrograph: an ultra high-resolution spectrometer for tender RIXS. https://doi.org/10.1107/s1600577521003805

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