Ultrafast demagnetization in bulk nickel induced by X-ray photons tuned to Ni $M_{3}$ and $L_3$ absorption edges

TL;DR

This paper provides theoretical predictions for ultrafast X-ray-induced demagnetization in bulk nickel, highlighting the influence of the d-band density of states and suggesting experimental directions.

Contribution

It introduces a theoretical analysis of X-ray induced demagnetization in nickel at specific absorption edges, emphasizing the role of the d-band peak above the Fermi level.

Findings

The d-band peak above the Fermi level significantly enhances demagnetization signals.

X-ray photon energies tuned to Ni M3 and L3 edges produce strong demagnetization effects.

Theoretical predictions suggest stronger effects in nickel than in cobalt.

Abstract

Studies of light-induced demagnetization started with the experiment performed by Beaupaire et al. on nickel. Here, we present theoretical predictions for X-ray induced demagnetization of nickel, with X-ray photon energies tuned to its $M_3$ and $L_3$ absorption edges. We show that the specific feature in the density of states of the d-band of Ni, a sharp peak located just above the Fermi level, strongly influences the change of the predicted magnetic signal, making it stronger than in the previously studied case of cobalt. We believe that this finding will inspire future experiments on magnetic processes in X-ray irradiated nickel.