MAGNETIC COUPLING IN PSEUDOMORPHIC 2ML OVERLAYERS AND SANDWICH SUPERLATTICE STRUCTURES OF Cr, Mn, Fe, Co AND Ni ON FCC Cu(001)

Abstract

The magnetic coupling in pseudomorphic overlayer and sandwich structures of 2ML magnetic ultrathin films on Cu (001) substrate is investigated by using spin-polarized density functional theory. The 2ML magnetic overlayers have significant magnetic moment except CrNi overlayer for which magnetic moment is very small (0.004 μB/ atom ). The overlayers having one layer of Cr turn out to be antiferromagnetically coupled except CrNi/Cu overlayer which has ferromagnetic coupling. All other overlayers have ferromagnetic coupling. In contrast to ferromagnetic MnMn/Cu overlayer, the Cu/MnMn/Cu sandwich has antiferromagnetic coupling. Similar to CrFe/Cu overlayer, the Cu/CrFe/Cu sandwich has antiferromagnetic coupling, while all other sandwiches have ferromagnetic coupling. The sandwiched structures have reduced magnetic moment as compared to their overlayer counterparts. The MnMn , MnFe , and MnCo sandwiches have highly reduced magnetic moment as compared to their overlayer counterparts.