Multi-Orbital Interactions and Spin Polarization in Single Rare-Earth Adatoms

Massine Kelai; Stefano Reale; Roberto Robles; Jaehyun Lee; Divya Jyoti; Philippe Ohresser; Edwige Otero; Fadi Choueikani; Fabrice Scheurer; Nicolás Lorente; Deung-Jang Choi; Aparajita Singha; Fabio Donati

arXiv · 2405.15229

Multi-Orbital Interactions and Spin Polarization in Single Rare-Earth Adatoms

Massine Kelai·Stefano Reale·Roberto Robles·Jaehyun Lee·Divya Jyoti·Philippe Ohresser·Edwige Otero·Fadi Choueikani·Fabrice Scheurer·Nicolás Lorente·Deung-Jang Choi·Aparajita Singha·Fabio Donati

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Abstract

Surface-adsorbed rare-earth nanostructures are ideal platforms to investigate the interplay between intra-atomic interactions and multi-orbital spin configurations. However, addressing these properties has posed severe experimental and theoretical challenges. Here, we use the orbital selectivity offered by X-ray absorption spectroscopy to quantify the Coulomb integrals of Nd atoms on conductive surfaces, as well as the variation of individual orbital occupation upon cluster nucleation. Using X-ray magnetic circular dichroism we identify magnetic moments of the order of \MK{few tens of}~$\mu_{\rm{B}}$ at the $5d$ orbitals and their magnetic coupling with the $4f$ spins. Our results validate orbital-resolved X-ray spectroscopy as a reliable method for quantifying complex multi-orbital interactions in surface-adsorbed lanthanides.

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Massine Kelai, Stefano Reale, Roberto Robles, Jaehyun Lee, Divya Jyoti, Philippe Ohresser, Edwige Otero, Fadi Choueikani, Fabrice Scheurer, Nicolás Lorente, Deung-Jang Choi, Aparajita Singha, Fabio Donati. 2024-05-24. Multi-Orbital Interactions and Spin Polarization in Single Rare-Earth Adatoms. https://arxiv.org/abs/2405.15229

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