Cyclotron resonance in bilayer graphene.
We present the first measurements of cyclotron resonance of electrons and holes in bilayer graphene. In magnetic fields up to B=18 T, we observe four distinct intraband transitions in both the conduction and valence bands. The transition energies are roughly linear in B between the lowest Landau levels, whereas they follow square root[B] for the higher transitions. This highly unusual behavior represents a change from a parabolic to a linear energy dispersion. The density of states derived from our data generally agrees with the existing lowest order tight binding calculation for bilayer graphene. However, in comparing data to theory, a single set of fitting parameters fails to describe the experimental results.
Henriksen
E A
EA
Department of Physics, Columbia University, New York, New York 10027, USA. erik@phys.columbia.edu
Jiang
Z
Z
Tung
L-C
LC
Schwartz
M E
ME
Takita
M
M
Wang
Y-J
YJ
Kim
P
P
Stormer
H L
HL