Assume with the tight-binding framework, that we need to consider only 1 Wannier orbital from each site. The energy level of this Wannier orbital is e0 (i.e. alpha = -e0). In addition, we retain the nearest-neighbor tight-binding matrix t (i.e. gamma = -t )
(a) Determine the energy dispersion for a bcc strucutre and an fcc structure where a is the length of the cubic cell.
(b) Determine the effective mass near k = 0 for each case