First-principles calculations of dielectric and optical properties of MgB2

作者：Balassis A^*; Chulkov E V; Echenique P M; Silkin V M

来源：Physical Review B, 2008, 78(22): 224502.

DOI：10.1103/PhysRevB.78.224502

• ab initio calculations
• band structure
• density functional theory
• dielectric function
• exchange interactions (electron)
• extinction coefficients
• magnesium compounds
• refractive index
• RPA calculations
• superconducting materials

We report on the results of calculation of low-energy dielectric response and optical properties of MgB2. The calculations have been performed with full inclusion of the ab initio electron band structure making use of random-phase and time-dependent local-density approximations. The role of local-field and exchange-correlation effects in MgB2 dielectric function is thoroughly examined. Index of refraction, extinction coefficient, and normal-incidence reflectivity exhibiting strong anisotropy were calculated for electromagnetic waves polarized along the a(*) and c(*) axes by using the evaluated electron-density-response functions. Our results are in good agreement with recent x-ray and optical measurements performed on MgB2 single crystals.

• 出版日期2008-12