Relativistic effects on the structural and transport properties of III–V compounds: A first-principles study

We have performed ab initio self-consistent calculations based on the full potential linear augmented plane-wave method (FP-LAPW) with the local density approximation (LDA) and the Generalised Gradient Approximation (GGA) to investigate the relativistic effects, on the structural, and transport properties of III–V compounds. We found that the stabilisation (destabilisation) of s, p∗(p,d) orbital energies (i) reduces the lattice parameters of III–V compounds, considerably reduces the band gaps of the III–V compounds, (ii) reduces the effective masse, and (iii) induces strong spin orbit splitting of heavier III–V compounds. Furthermore we circumvent the negative gap problem by combining non relativistic and Engel–Vosko approximations. These approaches open the gap of the most III–V compounds, and leads to a realistic band structure.