First-principles study of the photovoltaic properties of orthorhombic Ca2Si1-xPx (0<x<0.5)

Electronic structure and optical properties of simple orthorhombic Ca2Si1-xPx have been calcu-lated by the first-principles methods. The result shown that the band gap of the simple ortho-rhombic Ca2Si1-xPx was still a direct semiconductor and the band gap was increased with the concentration of P impurity increased. The dielectric constant and refractive index were in-creased with the concentration of P impurity increased. The extinction coefficient, the reflectivi-ty, the absorption and the conductivity have significant changed in the energy range of 0eV~1eV. Therefore, Transmission property of energy band structure and optical properties of simple or- thorhombic Ca2Si1-xPx were changed by changing the impurity concentration. It is a useful method for modulating photoelectric transmission property of the simple orthorhombic Ca2Si1-xPx.