Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electron-electron interaction and electron-hole asymmetry in bilayer
  graphene   We report precision measurements of the effective mass m* in high-quality
bilayer graphene using the temperature dependence of the Shubnikov-de Haas
oscillations. In the density range of 0.7 x 10^12/cm^2 < n < 4.1 x 10^12 /cm^2,
both the hole mass m*_h and the electron mass m*_e increase with increasing
density, demonstrating the hyperbolic nature of the bands. The hole mass m*_h
is approximately 20-30% larger than the electron mass m*_e. Tight-binding
calculations provide a good description of the electron-hole asymmetry and
yield an accurate measure of the inter-layer hopping parameter v_4 = 0.063.
Both m*_h and m*_e are substantially suppressed compared to single-particle
values, providing clear and unprecedented evidence for the strong
renormalization effect of electron-electron interaction in the band structure
of bilayer graphene.

16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph