where the interaction for absorption of the
electromagnetic wave is normalized to one photon in the
unit volume, e is the polarization of the impinging proton
with the wave vector k, 0 e is the dielectric constant of
vacuum, 0 y is the basic state of an atom. We have
denoted the integral in the | | by J and the constant before
| | by C. We also supposed that the energy of impinging
photon is sufficiently big that change of vector k during
the desintegration of the pseudoelectron is very small. It
is well-known that the description conductivity in
graphene can be approximated in the tight-binding
interaction Hamiltonian.
We consider here the case with electrons in magnetic
field as an analog of the Landau diamagnetism. So, we
take the basic function for one electron in the lowest
Landau level, as