An ab initio study of the magnetocrystalline anisotropy and magnetoelastic coupling of half-metallic CrO2

[摘要] First-principles density functional calculations of the total energy, magnetic moments and magnetocrystalline anisotropy energy (MAE) of CrO2 as a function of both volume and uniaxial strain along the c-axis have been performed. The highly accurate all-electron full-potential linearized augmented plane wave method and the generalized gradient approximation to the exchange-correlation potential are used. The calculated structural properties (lattice constants and unit cell volume) are in excellent agreement with experiments (with 0.5%). The calculated bulk and Young's modulii are 2.56 and 2.02 Mbar, respectively. The calculated MAE increases almost linearly with the uniaxial strain and remains positive in the strain range of -4-4%. Thus, the calculations predict that the easy magnetization axis is along the c-axis, in agreement with experiments. However, the calculated anisotropy constant is about six times larger than the measured value. The calculated magnetoelastic coupling constant is 1.2 x 10(7) erg/cm(3) and the magnetostriction coefficient lambda(001) is -2.59 x 10(-5). (C) 2004 Elsevier B.V. All rights reserved.

[发布日期] 2004-11-01

[效力级别]  Proceedings Paper

[关键词] CrO2;magnetocrystalline anisotropy;magnetoelastic coupling;magnetostriction