Fermi-surface and electron correlation in Al studied by Compton scattering

• Published in: The Journal of physics and chemistry of solids 2000-03, Vol.61 (3), p.397-401
• Main Authors: Suortti, P., Buslaps, T., Honkimäki, V., Metz, C., Shukla, A., Tschentscher, Th, Kwiatkowska, J., Maniawski, F., Bansil, A., Kaprzyk, S., Kheifets, A.S., Lun, D.R., Sattler, T., Schneider, J.R., Bell, F.
• Format: Article
• Language: English
• Subjects: Compton profile; D. Fermi surface
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/S0022-3697(99)00324-8

We have studied the electron-momentum density distribution in Al using the coincidence as well as the conventional high-resolution Compton scattering technique. In order to interpret the results, corresponding band theory based computations of the electron momentum density (EMD) and the Compton profiles (CPs) have been carried out. Our focus here is on determining the size of the break Z F in the EMD at the Fermi momentum. For this purpose, differences between measurements and theoretical predictions are analyzed in terms of a simple model for describing electron correlation effects which are missing from the independent particle band theory framework; the model involves Z F as the only adjustable parameter. A good fit with the coincidence measurements is obtained for Z F of about 0.7, while the CP data yields Z F=0.7 to 0.8. This study suggests that, in sharp contrast to the case of Li where recent high-resolution Compton work indicates Z F≈0, the standard picture of the interacting electron gas is substantially correct in Al.