# Large effect of the metal substrate on the magnetic anisotropy of Co on hexagonal Boron Nitride

## TL;DR

This study investigates how different metal substrates influence the magnetic anisotropy of cobalt atoms on hexagonal boron nitride, revealing substrate-dependent variations in magnetic properties through combined experimental and theoretical approaches.

## Contribution

It provides a comprehensive analysis of substrate effects on Co magnetic anisotropy on h-BN, integrating spectroscopy, DFT calculations, and many-body models to identify adsorption site influences.

## Key findings

- Large out-of-plane anisotropy on h-BN/Ru(0001)
- Near isotropic magnetic behavior on h-BN/Ir(111)
- Different adsorption sites cause the anisotropy variation

## Abstract

We combine x-ray absorption spectroscopy (XAS), x-ray magnetic circular dichroism (XMCD) and x-ray magnetic linear dichroism (XMLD) data with first principles density functional theory (DFT) calculations and a multiorbital many body Hamiltonian approach to understand the electronic and magnetic properties of Co atoms adsorbed on h-BN/Ru(0001) and h-BN/Ir(111). The XAS line shape reveals, for both substrates, an electronic configuration close to $3d^8$, corresponding to a spin $S = 1$. Magnetic field dependent XMCD data show large (14 meV) out-of-plane anisotropy on h-BN/Ru(0001), while it is almost isotropic (tens of $\mu$eV) on h-BN/Ir(111). XMLD data together with both DFT calculations and the results of the multiorbital Hubbard model suggest that the dissimilar magnetic anisotropy originates from different Co adsorption sites, namely atop N on h-BN/Ru(0001) and 6-fold hollow on h-BN/Ir(111).