Question

3. Graphene bandstructure Graphene is a good example of 2D system with two atoms per unit cell (a) Write the simplified form of Hamiltonian using given vector notation. Consider the basis function is a Bloch wavefunction (b) From the eigenvalue equation, assume E(k) Eo ± |hol Which points in k-space satisfy ho = 0? 27T (c) One example of the answer for (b) is .(0,Using the Taylor expansion near that k-space point to simplify ho(kx,ky) and write the eigenvalue with the result.

Answer 1

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