Open AccessAb initio investigation of anisotropic optical properties of MgB2
Author(s) -
Shang Xue-Fu,
Xinyong Tao,
Wenbin Chen,
Hui-Xian Chen,
Miao Wang,
Ming-Qiu Tan
Publication year - 2008
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.57.5838
Subject(s) - optical conductivity , spectral line , anisotropy , superconductivity , materials science , conductivity , condensed matter physics , ab initio , ab initio quantum chemistry methods , optical spectra , molecular physics , atomic physics , physics , optics , quantum mechanics , molecule
The density functional theory and full-potential linearized augmented plane wave (FLAPW) method are used to study the anisotropic optical properties of superconductor MgB2. The optical conductivity spectrathe reflectivity spectra and electron energy loss spectra have been calculated. The calculated optical conductivity spectra along xx-axis display quite different features in comparison with that along the zz-axiswhile the reflectivity spectra coincide well with the corresponding electron energy loss spectraespecially with respect to the characteristic peaks. In the optical conductivity spectrathe first intra-band absorption peak along xx-axis appears at 20000cm-1 while along zz-axis it appears at a high frequency of about 40000cm-1. In order to simulate the temperature effect in these spectrathe Lorentz expansion (δ=0.10eV) is added to the optical matrix elements in the calculation for 0K. In comparison with existing experimental dataa minor discrepancy of 1000cm-1 (0.124eV) has been found in the calculated optical spectra.