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Observation of Iron Spin-States using Tabletop X-ray Emission Spectroscopy and Microcalorimeter Sensors
Published
Author(s)
Young Il Joe, Galen C. O'Neil, Luis Miaja Avila, Joseph W. Fowler, Kevin L. Silverman, Daniel S. Swetz, Joel N. Ullom, Ralph Jimenez
Abstract
X-ray emission spectroscopy (XES) is a powerful probe of the electronic and chemical state of elemental species embedded within more complex compounds. X-ray sensors that combine high resolving power and high collecting efficiency are desirable for photon-starved XES experiments such as measurements of dilute, gaseous, and radiation-sensitive samples, time-resolved measurements, and in-laboratory XES where the exciting x-ray fluxes available are much less intense than at large facilities. To assess whether arrays of cryogenic microcalorimeters will be useful in photon- starved XES scenarios, we demonstrate that these emerging energy-dispersive sensors can detect the spin-state of two different iron compounds, Fe2O3 and FeS2, from the perturbing effect of the local 3d magnetic moment on the Kα and Kβ x-ray transitions. The measurements were conducted using a picosecond pulsed laser-driven plasma as the exciting x-ray source. The use of this tabletop source suggests that time-resolved in-laboratory XES will be possible in the future. We also present simulations of Kα and Kβ spectra that reveal the spin-state sensitivity of different combinations of sensor resolution and accumulated counts. These simulations predict that use of the Kα complex is attractive, that our current experimental apparatus can perform time-resolved XES measurements on some samples on timescales of a few 10s of hours per time delay, and that anticipated improvements in source and detector technology will enable in-laboratory, time-resolved XES on a broad range of samples on timescales near an hour.
Citation
Journal of Physics B-Atomic Molecular and Optical Physics
, Y.
, O'Neil, G.
, Miaja, L.
, Fowler, J.
, Silverman, K.
, Swetz, D.
, Ullom, J.
and Jimenez, R.
(2015),
Observation of Iron Spin-States using Tabletop X-ray Emission Spectroscopy and Microcalorimeter Sensors, Journal of Physics B-Atomic Molecular and Optical Physics, [online], https://doi.org/10.1088/0953-4075/49/2/024003
(Accessed October 20, 2025)