Improved Calculation of the Electronic and Optical Properties of Tetragonal Barium Titanate

• Published in: Journal of electronic materials 2014-05, Vol.43 (5), p.1443-1449
• Main Authors: Siraji, Ashfaqul Anwar, Alam, M. Shah
• Format: Article
• Language: English
• Subjects: Barium; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Dielectric, piezoelectric, ferroelectric and antiferroelectric materials; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electron states; Electronics; Electronics and Microelectronics; Exact sciences and technology; Instrumentation; Materials Science; Methods of electronic structure calculations; Optical and Electronic Materials; Optical properties; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Physics; Solid State Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-014-3096-3

The electronic and optical properties of tetragonal barium titanate (BaTiO 3 ) have been investigated by use of first-principles density functional theory on a plane wave basis, by use of norm-conserving pseudopotentials in the localized density approximation. For accuracy, experimental lattice parameters reported in the literature were used. The band structure, total and partial density of states (DOS), and Born effective charges of tetragonal BaTiO 3 were obtained from first-principles calculations. The partial DOS and Born effective charges indicate that the Ti–O bonds are partially covalent and the Ba–O bonds are partially ionic. The complex dielectric functions for ordinary and extraordinary optical polarization were calculated, and were in reasonable agreement with those from previous first-principles calculations. The refractive index, extinction coefficient, reflectivity, and energy-loss spectrum for both types pf polarization were calculated from the complex dielectric function; the results obtained were an improvement on other published results.