Adatoms in Graphene Antonio H. Castro Neto

1. Adatoms in GrapheneAntonio H. Castro Neto Trieste, August 2008

2. Outline • Coulomb impurity in graphene • Vitor M. Pereira, Johan Nilsson, AHCN • Phys.Rev.Lett. 99, 166802 (2007); • Vitor M. Pereira, Valeri Kotov, AHCN • Phys. Rev. B 78, 085101 (2008). • Anderson impurity in graphene • Bruno Uchoa, Valeri Kotov, Nuno Peres, AHCN • Phys. Rev. Lett. 101, 026805 (2008); • Bruno Uchoa, Chiung-Yuan Lin, Nuno Peres, AHCN • Phys.Rev.B 77, 035420 (2008)‏.

5. 6 NO 2 2 4 (1/k)  (103 cm2/Vs) 1 2 0 0 0 1 2 -40 -20 0 20 40 Vg (V) Nim (1012 cm-2) Controlling scattering Geim’s group

6. 10 10 10 10 16 8 8 8 8 12 4e2/h smin (e2/h) 6 6 6 6 conductivity (mS) conductivity (mS) conductivity (mS) conductivity (mS) 8 4e2/ph X 2 4 4 4 4 4 2 2 2 2 0 0 0 0 0 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 -50 -50 -50 -50 0 0 0 0 50 50 50 50 Tail Mobility (m2/V sec) Vg (V) Vg (V) Vg (V) Vg (V) Kim’s group

7. Artificial structures: Chemistry, engineering, material science How do adatoms modify graphene’s properties ? Hashimoto et al. Nature 430, 870 (04)

8. Pereira et al., Phys.Rev.Lett. 99, 166802 (2007);

9. Coupling 3D Schroedinger

10. Undercritical Supercritical

12. Andrei’s group

14. HIC Neutron stars

17. E T>T K N(E) Anderson’s Impurity Model

19. Non-interacting: U=0 V=0 Broadening Energy Energy

20. Mean-Field

22. U = 1 eV n_up n_down V=1eV, e0=0.2 eV The impurity moment can be switched on and off!

23. U = 40 meV U = 0.1 eV

24. Conclusions • Impurities in graphene behave in an unusual way when compared to normal metals and semiconductors. • One can test theories of nuclear matter under extreme conditions. • Control of the magnetic moment formation of transition metals using electric fields.