First-principles determinations of magneto-crystalline anisotropy and magnetostriction in bulk and thin-film transition metals

Recent developments in the first-principles determination of magneto-crystalline anisotropy (MCA) and magnetostrictive coefficients in transition metal systems are reviewed. With the aid of our newly developed state tracking and torque approaches, high numerical stability can be achieved for the MCA energy, the essential ingredient of the magnetostriction. Very smooth monotonic behavior of the MCA energy with respect to the lattice strain was found for most of the systems studied. The calculated magnetostrictive coefficients are positive for BCC Fe and FCC Co but negative for FCC Ni - a result which agrees well with experiments. This can be explained simply through the strain induced d-band broadening and shifting. For Co/Cu(0 0 1), Co/Pd(0 0 1) and Co/Pd(1 1 1) thin films, the magnetostrictive coefficients are found to be very sensitive to the change of substrates and even orientation. (C) 1998 Elsevier Science B.V. All rights reserved.