Akademik Məlumat İdarəetmə Sistemi
Japanese Journal of Applied Physics, vol.47, no.10 PART 2, pp.8182-8187, 2008 (SCI-Expanded, Scopus)
The electronic energy-band structure of the room temperature phase of the ternary layered TlGaSe2 has been approached using linearized augmented plane wave (LAPW) method. Band structure and dielectric function have been calculated. This function has also been obtained in a wide range of photon energies from 0.76 to 6.5 eV by using spectroscopic phase modulated ellipsometry and a good agreement between the calculated and measured values has been observed. As derived from the used LAPW wave function set, the valence band top, occupying the center of the Brillouin zone originates from Tl 6s and Se 4p anti-bonding states, while the conduction band bottom, occupying a shifted-from-the center position on Γ-Y symmetry line is due to Tl 6p and Se 4p anti-bonding states. Higher than this bottom by 50meV, there is one more conduction band minimum in the center of the Brillouin zone. It has been shown that the calculated dielectric function accounts for all polarization peculiarities of the direct band-gap transitions in TlGaSe2 at room temperature. © 2008 The Japan Society of Applied Physics.