Optical Properties of α- Revealed by ab initio Calculations

Gboyega A. Adebayo (1, 2) , Bede C. Anusionwu (3)

1 ICTP - Abdus Salam International Centre for Theoretical Physics [Trieste]
2 Department of Physics
3 Department of Physics

Detailed optical functions and optical properties of a α-monoclinic phase of Selenium α- Se are presented over a wide range of angular frequencies ωby first-principles calculations. An optical band gap of 2.05eV and a mobility gap of 2.17eV ±0.05 are observed in the present calculations. The imaginary part of the dielectric function has been obtained from the frequency dependent dielectric matrix and the use of the Kramers-Kronig (KK) relation allows us to determine the real part of the dielectric function. Optical functions and optical properties revealed the occurrence of a long range order in Se. For the first time, infrared and absorption spectra of monoclinic -Se were studied using the Kramers-Kronig (KK) relation by ab initio method. And lastly, detailed studies of other dielectric related optical constants such as reflectivity, transmission, reflection and absorption coefficients were also presented.

Mots clés: Density Functional Theory; Electronic Structure; Infrared Spectra; Amorphous Semiconductors; First Principles Theory; Ab initio simulation; Elemental Semiconductors

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Gboyega A. Adebayo, Bede C. Anusionwu. Optical Properties of α- Revealed by ab initio Calculations. Journal of Physics and Chemistry of Solids, 2010, 71 (12), pp.1690. ⟨10.1016/j.jpcs.2010.08.022⟩. ⟨hal-00691336⟩