• Journal of the Korean Magnetics Society
• /
• v.18 no.4
• /
• pp.159-162
• /
• 2008

The phenomenon of magnetostriction occurs in magnetic systems when the temperature is changed or the external magnetic field is applied. It is known that the magnetostriction observed in rare-earth elements and compounds is well described by the crystal-field striction and the exchange striction. In this review paper, we discuss the standard theory for the magnetostriction which includes the crystal-field and the exchange interaction.

• Journal of the Korean Magnetics Society
• /
• v.26 no.2
• /
• pp.39-44
• /
• 2016

Determination of the structural, electronic, and magnetic properties of the magnetically doped bismuth-telluride alloys are drawing lots of interest in the fields of the thermoelectric application as well as the research on magnetic interaction and topological insulator. In this study, we performed the first-principles electronic structure calculations within the density functional theory for the Gd doped bismuth-tellurides in order to study its magnetic properties and magnetic phase stability. All-electron FLAPW (full-potential linearized augmented plane-wave) method is employed and the exchange correlation potentials of electrons are treated within the generalized gradient approximation. In order to describe the localized f-electrons of Gd properly, the Hubbard +U term and the spin-orbit coupling of the valence electrons are included in the second variational way. The results show that while the Gd bulk prefers a ferromagnetic phase, the total energy differences between the ferromagnetic and the antiferromagnetic phases of the Gd doped bismuth-telluride alloys are about ~1meV/Gd, indicating that the stable magnetic phase may be changed sensitively depending on the structural change such as defects or strains.