  We have evaluated the electromagnetic spectral function and its spectral
properties by computing the one-loop photon polarization tensor in presence of
magnetic field, particularly in a strong field approximation compared to the
thermal scale. When the magnetic scale is higher than the thermal scale the
lowest Landau level (LLL) becomes effectively (1+1) dimensional strongly
correlated system that provides a kinematical threshold based on the mass
scale. Beyond this threshold the photon strikes the LLL and the spectral
strength starts with a high value due to the dimensional reduction and then
falls off with increase of the photon energy due to LLL dynamics in a strong
field approximation. This strongly enhances the dilepton rate over the thermal
perturbative leading order (Born) rate at very low invariant mass. We have also
investigated the electromagnetic screening by computing the Debye screening
mass and it depends distinctively on three different scales (mass of the
quasiquark, temperature and the magnetic field strength) of a hot magnetized
system. The mass dependence of the Debye screening supports the occurrence of a
magnetic catalysis effect in the strong field approximation.
