Influence of the crystal structure and chemical order on the magnetic and magneto-optical properties of equiatomic CoPt alloy

The influence of the structure-dependent electronic effects on the magnetic, magneto-optical (MO), and anisotropic properties of equiatomic CoPt alloy was modeled with the use of fully relativistic linear-muffin-tin-orbital calculations. We found large differences between the MO spectra of the alloy of the AuCu (L1(1)) and CuPt (L1(0)) superlattice type structures, as well as a strong sensitivity of the spectra on the degree of chemical order. Very good agreement between the experimental and theoretical spectra for both a partially ordered and a fully disordered alloy, modeled by a Monte Carlo simulation, is found, demonstrating the applicability of the theoretical approach. (C) 2002 American Institute of Physics.