Pressure induced electronic and optical properties of rutile SnO2 by first principle calculations

Tin dioxide (SnO2) is the most important semiconductor material due to its large number of technological applications. In this work we carried out the electronic and optical properties under pressure of rutile SnO2. The ultra-soft pseudopotential method is used by employing the local density approximation functional proposed by Ceperley-Alder and Perdew-Zunger to calculate the exchange correlation potential within the framework of density functional theory. Firstly we optimized the structure to obtain the ground state energy of the system with the increase of cutoff energy (Fig. 1 (b)). The investigated band structure and density of states show that energy bandgap is increasing with the increase of pressure due to the movement of valence bands from higher to low energy levels and the conduction bands from lower to higher energy levels respectively (Fig. 1 (a)). The effect of pressure on lattice constants demonstrates the increase in lattice constants. Optical properties, comprising refractive index, dielectric function, absorption and energy loss spectrum are investigated. The obtained results are in good agreement with the previous reported theoretical and experimental results.