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arXiv · 2307.08862

X-ray Spectroscopy of a Rare-Earth Molecular System Measured at the Single Atom Limit in Room Temperature

Sarah Wieghold·Nozomi Shirato·Xinyue Cheng·Kyaw Zin Latt·Daniel Trainer·Richard Sottie·Daniel Rosenmann·Eric Masson·Volker Rose·Saw Wai Hla
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Abstract

We investigate the limit of X-ray detection at room temperature on rare-earth molecular films using lanthanum and a pyridine-based dicarboxamide organic linker as a model system. Synchrotron X-ray scanning tunneling microscopy is used to probe the molecules with different coverages on a HOPG substrate. X-ray-induced photocurrent intensities are measured as a function of molecular coverage on the sample allowing a correlation of the amount of La ions with the photocurrent signal strength. X-ray absorption spectroscopy shows cogent M4,5 absorption edges of the lanthanum ion originated by the transitions from the 3d3/2 and 3d5/2 to 4f orbitals. X-ray absorption spectra measured in the tunneling regime further reveal an X-ray excited tunneling current produced at the M4,5 absorption edge of La ion down to the ultimate atomic limit at room temperature.

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Sarah Wieghold, Nozomi Shirato, Xinyue Cheng, Kyaw Zin Latt, Daniel Trainer, Richard Sottie, Daniel Rosenmann, Eric Masson, Volker Rose, Saw Wai Hla. 2023-07-17. X-ray Spectroscopy of a Rare-Earth Molecular System Measured at the Single Atom Limit in Room Temperature. https://arxiv.org/abs/2307.08862

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