Electronic, optical, and mechanical properties of BN, AlN, and InN with zinc-blende structure under pressure

In this work, the electronic, optical, and mechanical properties of BN, AlN, and InN under the action of pressure are calculated. For each of these compounds, the energy band structure, band gaps (E_g^L, E_g^Γ,E_g^X), refractive index (n), dielectric constants (ε_∞ , ε₀), elastic constants (C₁₁, C₁₂,C₄₄), and relevant parameters such as bulk (B_u), shear (S_h), and Young's (Y₀) moduli are studied, and other important parameters such as bond-stretching (α), bond-bending (β) force constant, internal-strain parameter (ζ), effective charges (e_T^*, Z^*), anisotropy factor (I_s), Poisson's ratio (P_o), Cauchy ratio (C_a), the ductility index (μ_D), and linear compressibility (C₀) are also calculated. The effects of pressure on all studied properties are investigated. Our results are in good agreement with the available experimental and theoretical data for BN, AlN, and InN.