Tuning the Curie temperature of FeCo compounds by tetragonal distortion

Abstract

Combining density-functional theory calculations with a classical Monte Carlo method, we show that for B2-type FeCo compounds tetragonal distortion gives rise to a strong reduction of the Curie temperature $T_{\mathrm{C}}$. The $T_{\mathrm{C}}$ monotonically decreases from 1575 K (for $c/a=1$) to 940 K (for $c/a=\sqrtwo$). We find that the nearest neighbor Fe-Co exchange interaction is sufficient to explain the $c/a$ behavior of the $T_{\mathrm{C}}$. Combination of high magnetocrystalline anisotropy energy with a moderate $T_{\mathrm{C}}$ value suggests tetragonal FeCo grown on the Rh substrate with $c/a=1.24$ to be a promising material for heat-assisted magnetic recording applications.

4 pages, 2 figures

References in corpus (5)

• Role of the conduction electrons in mediating exchange interactions in Heusler alloys
• Theory of quasiparticle spectra for Fe, Co, and Ni: bulk and surface
• First-principles prediction of high Curie temperature for ferromagnetic bcc-Co and bcc-FeCo alloys and its relevance to tunneling magnetoresistance
• Magnetic anisotropy energy of disordered tetragonal Fe-Co systems from ab initio alloy theory
• Strong magnon softening in tetragonal FeCo compounds

Cited by in corpus (2)

• Paramagnetic molecule induced strong antiferromagnetic exchange coupling on a magnetic tunnel junction based molecular spintronics device
• Coulomb correlations and magnetic properties of L1${}_0$ FeCo: a DFT+DMFT study