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arXiv · 2305.13727

Roughness-induced magnetic decoupling at organic-inorganic interface

Hiroki Ono·Yoshitaka Umeda·Kaito Yoshida·Kenzaburo Tsutsui·Kohei Yamamoto·Osamu Ishiyama·Hiroshi Iwayama·Eiken Nakamura·Toshihiko Yokoyama·Masaki Mizuguchi·Toshio Miyamachi
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Abstract

We have investigated structural, electronic and magnetic properties of H$_2$Pc on Fe$_2$N/Fe using low-energy electron diffraction and soft x-ray absorption spectroscopy/x-ray magnetic circular dichroism. Element specific magnetization curves reveal that the magnetic coupling with H$_2$Pc enhances the perpendicular magnetic anisotropy of Fe$_2$N/Fe at the H$_2$Pc coverage of 1 molecular layer. However, adding two and three molecular layers of H$_2$Pc reverts the shape of magnetization curve back to the initial state before H$_2$Pc deposition. We successfully link appearance and disappearance of the magnetic coupling at the H$_2$Pc-Fe$_2$N/Fe interface with the change of hybridization strength at N sites accompanied by the increase in the H$_2$Pc coverage.

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Hiroki Ono, Yoshitaka Umeda, Kaito Yoshida, Kenzaburo Tsutsui, Kohei Yamamoto, Osamu Ishiyama, Hiroshi Iwayama, Eiken Nakamura, Toshihiko Yokoyama, Masaki Mizuguchi, Toshio Miyamachi. 2023-05-23. Roughness-induced magnetic decoupling at organic-inorganic interface. https://doi.org/10.1021/acs.jpcc.3c05966

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