3 research outputs found
The quantum Hall effect in graphene samples and the relativistic Dirac effective action
We study the Euclidean effective action per unit area and the charge density
for a Dirac field in a two--dimensional spatial region, in the presence of a
uniform magnetic field perpendicular to the 2D--plane, at finite temperature
and density. In the limit of zero temperature we reproduce, after performing an
adequate Lorentz boost, the Hall conductivity measured for different kinds of
graphene samples, depending upon the phase choice in the fermionic determinant.Comment: Conclusions extended. References added. 9 pages. 1 figur
Parity-odd effects and polarization rotation in graphene
We show that the presence of parity-odd terms in the conductivity (or, in
other words, in the polarization tensor of Dirac quasiparticles in graphene)
leads to rotation of polarization of the electromagnetic waves passing through
suspended samples of graphene. Parity-odd Chern-Simons type contributions
appear in external magnetic field, giving rise to a quantum Faraday effect
(though other sources of parity-odd effects may also be discussed). The
estimated order of the effect is well above the sensitivity limits of modern
optical instruments.Comment: 8 page