Structure dependence of optical spectra of ferromagnetic Heusler alloy Ni–Mn–Ga

Abstract The influence of structural transformation on the optical properties of Heusler alloy Ni–Mn–Ga has been investigated by using Density Functional Theory code CASTEP. The calculated optical refractive and absorption spectra, the off-diagonal components of the dielectric function and the optical conductivity for L2 1 structure and the tetragonal phase show a noticeable structural dependence which were confirmed by the experiments (Y.V. Kudryavtsev et al., Phys. Rev. B 66 (2002) 115114).