The electron bandstructure for gallium arsenide (zincblende structure) was calculated using the program Quantum Espresso (version 5.3.0). GaAs is a compound semiconductor material with a direct bandgap of 1.424 eV. At the figure below, one can see that the bandgap in the calculation is a little smaller than expected, but the course of the lines correlates to comparative data (cf. SciRes) .
Zincblende structure of GaAs Source: Wikipedia
Density of states