%N 16
%X A metallic isolated band in the middle of the band gap of several III-V semiconductors has been predicted
as photovoltaic materials with the possibility of providing substantially enhanced efficiencies. We have investigated
the electronic band structures and lattice constants of GanAsmM and GanPmM with M5Sc, Ti, V, and
Cr, to identify whether this isolated band is likely to exist by means of accurate calculations. For this task, we
use the SIESTA program, an ab initio periodic density-functional method, fully self consistent in the localdensity
approximation. Norm-conserving, nonlocal pseudopotentials and confined linear combination of atomic
orbitals have been used. We have carried out a case study of GanAsmTi and GanPmTi energy-band structure
including analyses of the effect of the basis set, fine k-point mesh to ensure numerical convergence, structural
parameters, and generalized gradient approximation for exchange and correlation corrections. We find the
isolated intermediate band when one Ti atom replaces the position of one As ~or P! atom in the crystal
structure. For this kind of compound we show that the intermediate band relative position inside the band gap
and width are sensitive to the dynamic relaxation of the crystal and the size of the basis set.
%J Physical Review B
%D 2002
%L upm61428
%R 10.1103/PhysRevB.65.165115
%I American Physical Society
%T Ab initio electronic structure calculations for metallic intermediate band formation
in photovoltaic materials
%A Perla Wahnón Benarroch
%A César Tablero Crespo
%K Photovoltaic materials; intermediate band
%V 65
%P 165115-1-165115-10