Lattice dynamics properties of XAs (X=Al, Ga and In) with zinc-blende structure from first-principle calculations

Band structures, density of states, dielectric and vibrational properties of XAs (X=Al, Ga and In) alloys with zinc-blende structure have been studied using the density functional theory (DFT). The calculated lattice constants, band gap, static dielectric constants and phonon frequencies are all in good agreement with the available experimental data and other theoretical results. The calculated results show that Born effective charges ZB increase with cation mass. A similar tendency has been observed for phonon frequencies ωTO and ωLO. Calculation results prove that static dielectric constants ε(0) increase with atomic weight, i.e. in the sequences AlAs–GaAs–InAs, and show an inverse sequence for band gap.

► Dielectric and vibrational properties of XAs (X=Al, Ga, and In) have been studied.
► Dielectric constant ε2(ω) was determined from our calculated band structure.
► Results prove that static dielectric constants ε(0) increased with atomic weight.