First principles study of the structural, elastic, electronic and optical properties of CaSrTt (Tt=Si, Ge, Sn and Pb)

Saoudi, A.; Hachemi, A.; Hamida, Abdelhak Ferhat; Medkour, Y.; Reffas, M.; Hachemi, H.; Maamache, M.

doi:10.1016/j.ssc.2012.07.009

Cited by 4 publications

(1 citation statement)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dielectric function and refractive coefficient can be deduced by the Kramers-Kronig relation in the first BZ [25]; the real part and imaginary part in the complex dielectric function are defined as equations ( 9) and (10), respectively:…”

Section: Theoretical Methods Of Optical Propertiesmentioning

confidence: 99%

Effect of stress on electronic structure and optical properties of cubic Ca₂Ge

Cen¹,

Yang²,

Tian³

2023

Semicond. Sci. Technol.

View full text Add to dashboard Cite

In this work, the effect of stress on the electronic structure and optical properties of cubic Ca2Ge was investigated using first-principles method. It is found that under compressive stress Ca2Ge is a direct-gap semiconductor and the band gap decreases from 0.5477 eV @ 0 GPa to 0.1025 eV @ 15 GPa till 20 GPa at which Ca2Ge becomes a semimetal. Under tensile stress, it is otherwise an indirect-gap, and the band gap decreases to 0.3178 eV @ -10 GPa till -15 GPa where it is a metal. The dielectric constant increases exponentially under compression, while increases irregularly but monotonically under strain. The absorption edge shifts in low energy direction with increasing compressive stress, while the absorption maximum of Ca2Ge shifts in high energy direction before Ca2Ge becomes metal under tensile stress. The effect on absorption increases with increasing energy, the absorption edge exhibits strong absorption characteristics under tension. Reflectivity shows that Ca2Ge is a material with low reflectivity. The effects of stress modulation on the electronic structure and optical properties are determined based on the atomic population. Under tensile stress, there is no chemical bonding. When the compressive stress increases to 10 GPa, a chemical bond is formed, and the bond population and length decrease with increasing stress.

show abstract

Section: Theoretical Methods Of Optical Propertiesmentioning

confidence: 99%