Is the Fermi Level at E = 2ta for Tight-Binding Dispersion?

[Niles]

Homework Statement

Hi

Say I have the tight-binding dispersion given by E = -2ta cos(ka). When plotting this, then is it correct that the Fermi level is at the energies satisfying E = 2ta, i.e. a straight line in a (k,E) plot?

 

[Niles]

Sorry to bump this, but is someone able to confirm my approach?Niles.