Spin density in ferromagnetic nickel: a magnetic Compton scattering study

Abstract

The magnetic Compton profiles (MCPs) measured in the [100], [110], [111] and [112] directions in single-crystal nickel with an incident photon beam of energy 224 keV are presented and discussed. The momentum resolution achieved, of 0.43 atomic units, improves on previous studies by almost a factor of two, and facilitates the interpretation of the MCPs in terms of the underlying spin-dependent momentum densities. Calculations have been performed using the linear muffin-tin orbital method, within both the local spin-density approximation (LSDA) and the generalized gradient approximation (GGA). Comparison with experiment reveals the limitations of the LSDA at low momentum, where the GGA is better able to reproduce the contribution of the s-and p-like electrons. All of the calculations overestimate the moment associated with the d-like electrons, for momenta corresponding to the first Brillouin zone. We also confirm the existence of the so-called Umklapp shoulders, which derive from the Fermi surface topology.

Momentum space anisotropy of electronic correlations in Fe and Ni: An analysis of magnetic Compton profiles

“…It was remarked by Dixon et al [60] that all computed peaks at higher momenta E (3.3 a.u) and F (4.7 a.u.) are more visible than the corresponding maxima in the experiment.…”

Full-potential LAPW calculation of electron momentum density and related properties of Li

“…The advent of high intensity, high energy and well-polarized synchrotron sources and the spectrometers with high resolution (∼ 0.12a.u.) have resulted in revival of interest in this area [13][14][15] . On the theoretical side, high performance computing facilities have made it possible to perform calculations on a fine p-mesh with a better convergence criteria for the total energy and charge density self-consistency.…”

A self-consistent, relativistic implementation of the LSDA+DMFT method

“…In the range of the studied values of U qualitative and quantitative differences are seen in the Compton profiles depending weather the LSDA is supplemented with static or dynamical many-body corrections. An important message is that relativistic effects and electronic correlations may have a non-trivial interplay and dynamical correlations determine larger relativistic corrections in the electronic [71,72]. The experimental momentum resolution is 0.43 a.u., which was also used as Gaussian broadening parameter for the calculated MCP spectra.…”