graphene as a new page in solid state physics l.a. falkovsky landau institute for theoretical...

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Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

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Page 1: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

Graphene as a new page in Solid State Physics

L.A. FalkovskyLandau Institute for Theoretical Physics Institute of High Pressure Physics

Page 2: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

Graphene sample in the Hall conductivity experiment

Novoselov et al (2005)

Page 3: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

GraphiteWallace, PR 71, 622 (1947)McClure, PR 108, 612 (1957)Slonczewski, Weiss, PR 109 (1958)

NanotubesSaito, Fujita, Dresselhaus, Dresselhaus, PRB 46, 1804 (1992)

Page 4: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

2221 v yx pp ,

two-dimensional massless Dirac fermions

scm /810v

K

K’

graphene doped

Page 5: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

Novoselov et al (2005)Field-effect

2) universal minimal conductivity

22emin

1) conductivity proportional to the carrier density

3) universal optical conductivity

4)(

2eopt

Page 6: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

2

k=p±p±

Time and space dispersion of conductivity Falkovsky and Varlamov (2006)

g 2 2

T,kv,ω<<τ

10

Page 7: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

optical conductivity

T

0T

interband

intraband

T

Falkovsky and Pershoguba (2007)

Gusynin and Sharapov (2007)

Page 8: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

optical transmittance of graphene

z

x

r

t

Novoselov et al. (2008)

Page 9: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

graphene conductance

D. Basov et al (2008)

Page 10: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

x

y

X<0

U=0X<0

X>0

X>0

Klein’s paradox

U

x

Page 11: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

(2009)

Page 12: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

Bilayer graphene

field effect

bilayerMcCann, Fal’ko (2006-2007)

Novoselov et alOhta et alLi et alKuzmenko et alMak et al

2U

E=2U/d

d2

d2

electron dispersion

Page 13: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics
Page 14: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics

Mounet PRB (2005)

Graphite phonon modes

Page 15: Graphene as a new page in Solid State Physics L.A. Falkovsky Landau Institute for Theoretical Physics Institute of High Pressure Physics