Giant atomic magnetocrystalline anisotropy from degenerate orbitals around Fermi level

TL;DR

This paper demonstrates that specific p-element dimers and single adatoms on symmetry-matched substrates can achieve giant atomic magnetocrystalline anisotropy energies due to degenerate orbitals near the Fermi level, offering new design principles for nanostructures.

Contribution

It introduces a new understanding of how degenerate orbitals contribute to giant MAE and proposes a simplified quantum model for designing such nanostructures.

Findings

Achieved MAE of 72-200 meV in certain nanostructures.

Identified degenerate orbitals as key to large MAE.

Developed a quantum mechanical model to guide design.

Abstract

Nano-structures with giant magnetocrystalline anisotropy energies (MAE) are desired in designing miniaturized magnetic storage and quantum computing devices. Through ab initio and model calculations, we propose that special p-element dimers and single-adatom on symmetry-matched substrates possess giant atomic MAE of 72-200 meV with room temperature structural stability. The huge MAE originates from degenerate orbitals around Fermi level. More importantly, we developed a simplified quantum mechanical model to understand the principle on how to obtain giant MAE for supported magnetic structures. These discoveries and mechanisms provide a paradigm to design giant atomic MAE in nanostructures.