1. An introduction to x-ray absorption in graphene1 Pourya Ayria Supervisor: professor Saito 30 March 2013

2. Overview Graphene unite cell The nearest tight binding for graphene Dispersion relation for 1s orbital X-ray absorption in graphene Dipole vector

3. Graphene unit cell graphene (From chowdhury thesis) Brilloin zone

4. The nearest tight-binding for graphene The electronic dispersion of graphene

5. The nearest tight-bindig for graphene The electronic dispersion of graphene without considering overlap S=0 Eigenvalue

6. The calulated energy dispersion relation of 1s band of graphen 1s orbital energy -283.5 is considered under fermi level; however, some papares indicated that it is around -285. and t=0.1, S=0.

7. X-ray absorption in graphene: Dipole approximation: Matrix element for optical transition: are the tight binding wave function I p the energy density of electromagnetic wave. D dipole vector. P polarization of wave. The transition probability per one second as function of k: The absoption itensity I(E) : is the density of states at energy E

8. Dipole vector Dipole vector for transition to (matrix.f90) The oscillation strength is

9. Reference: Physical Properties of Carbon Nanotues, R.Saito,G.Dresselhaus,M.S Dresselhaus, Impreial college Press M.T.Chowdhury M.S Thesis Thanks dear hesky and nugraha. END