Electron momentum density in Cu0.9Al0.1

TL;DR

This study reconstructs the 3D electron momentum density in Cu0.9Al0.1 alloy using high-resolution Compton profiles and compares experimental results with first-principles calculations, revealing detailed Fermi surface features and electron correlation effects.

Contribution

It introduces a reconstruction method based on Radon transform and Jacobi polynomials for analyzing electron momentum density in disordered alloys.

Findings

Experimental density agrees with theoretical calculations.

Reveals detailed Fermi surface features.

Shows electron correlation effects in the alloy.

Abstract

A reconstruction technique based on the solution of the Radon transform in terms of Jacobi polynomials is used to obtain the 3D electron momentum density rho(p) from nine high-resolution Compton profiles (CPs) for a Cu0.9Al0.1 disordered alloy single crystal. The method was also applied to theoretical CPs computed within the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) first-principles scheme for the same nine orientations of the crystal. The experimental density rho(p) is in satisfactory agreement with the theoretical density and shows most details of the Fermi surface (FS) and exhibits electron correlation effects. We comment on the map of the FS obtained by folding the reconstructed rho(p) into the first Brillouin zone which yields the occupation number density, rho(k). A test of the validity of data via a consistency condition (within our reconstruction algorithm) as well as the propagation of experimental noise in the reconstruction of both rho(p) and rho(k) are investigated.