Hybrid functional applied to the study of properties of narrow and wide band gap semiconductors
|Jan Wróbel 1, Piotr Śpiewak 1,2, Krzysztof J. Kurzydlowski 1|
1. Warsaw University of Technology, Faculty of Materials Science and Engineering, Woloska 141, Warsaw 02-507, Poland
One shortcoming of Density Functional Theory (DFT) calculations based on the Local Density Approximation (LDA) or Generalized Gradient Approximation (GGA) is its failure to reproduce well the band gap of semiconductors and insulators. This deficiency of DFT is attributed to a large part to discontinuities in the derivative of the exchange-correlation energy. A way to overcome this problem is the application of a certain fraction of exact exchange (Hartree-Fock exchange) within DFT via a so-called hybrid functional.
The present paper will focus on DFT calculations based on the hybrid functional HSE06 . This method gives better estimate than standard approaches to DFT for properties of narrow and wide band gap semiconductors like Ge and ZnO . As the example the structure optimizations, calculations of electronic band gap, phonon dispersions and formation and migration energies of intrinsic point defects are performed and compared with LDA and/or GGA calculations and available experimental results.
 J. Heyd G. E. Scuseria and M. Ernzerhof J. Chem. Phys. 118 8207 (2003); and erratum ibid. 124 219906 (2006).
 J. Wróbel, J. Piechota, phys. stat. sol. (b) 244, No. 5, 1538 (2007); 244, No. 12, 4688 (2007)
Presentation: Poster at E-MRS Fall Meeting 2009, Symposium C, by Jan Wróbel
See On-line Journal of E-MRS Fall Meeting 2009
Submitted: 2009-05-16 19:35 Revised: 2009-06-07 00:44