AB-Initio Modeling of Intermediate Band Materials Based on Metal-Doped Chalcopyrite Compounds

Results of quantum calculations in M-doped chalcopyrite Cu₄ MGa₃S₈ (with M=Ti, V, Cr or Mn) are evaluated. The purpose of this work is the quest of a compound which possesses an isolated narrow partially-filled electronic band sited into the host semiconductor bandgap. The aforementioned material could be useful for designing novel solar cells with very high efficiency. Density functional theory calculations in the spin-polarized GGA approach have been carried out in all cases for obtain band dispersion diagrams and densities of electronic states. For the systems having Cr and Ti as dopants, where the results reveal promising features, an advanced DFT+U formalism has been used to ascertain their properties with higher certainty. Finally, after having reasoned that Cu₄MGa₃S₈ has the desired features, a prediction of its energetic feasibility has been formulated