Common data for questions 14 and 15: the tight binding energy dispersion (e-}) relation for electrons in a one-dimensional array of atoms having lattice constan

Common Data for Questions 14 and 15: The tight binding energy dispersion (E-}) relation for electrons in a one-dimensional array of atoms having lattice constant a and total length L is E Eo-B-2y cos ka), where E0, B and y are constants and k is the wave vector. Q14. The density of states of electrons (including spin degeneracy) in the band is given by (a) Ty a sin(ka) L (b) 2Ty a sin(ka) L (c) L (d) Tty a cos(ka) L 2Ty a cos(ka) Ans: a)