# Magneto-Crystalline Anisotropy of Fe, Co and Ni slabs from Density Functional Theory and Tight-Binding models

## TL;DR

This paper compares density functional theory and tight-binding methods to analyze the magneto-crystalline anisotropy of Fe, Co, and Ni slabs, revealing size-dependent behaviors and potential for tailored magnetic properties.

## Contribution

It provides a detailed comparison of MCA calculations from different computational methods and analyzes the effects of slab thickness and orientation on magnetic anisotropy.

## Key findings

- MCA oscillates with slab thickness due to finite size effects.
- Certain systems exhibit enhanced MCA, useful for magnetic applications.
- Rich features in k-space and band-filling influence MCA behavior.

## Abstract

We report magneto-crystalline anisotropy (MCA) calculations of Fe, Co and Ni slabs of various thicknesses and crystallographic orientations from two Density Functional Theory codes based either on a plane wave or a local atomic basis set expansion and a magnetic tight-binding method. We analyze the evolution of the MCA with the number of layers of the slabs. The decomposition of MCA into contributions of atomic sites helps understanding the oscillatory behaviour of the MCA with the slab thickness and highlights the role of finite size effects. We also identify some specific systems with enhanced MCA. A k-space as well as a band-filling analysis show very rich features of the MCA that could be used to tailor systems with enhanced magnetic properties. Finally this work can serve as a benchmark for MCA calculations.