  The interaction of high energy particles with atomic axes and planes allows
to observe in crystal various effects predicted by the quantum electrodynamics
of phenomena in strong electromagnetic field. In particular, the effect of
electron-positron pair production by gamma-quanta in a semi-uniform field was
observed for the first time in eightieth in CERN in the field of germanium
crystal axes. The high energy of LHC drastically widens the possibilities of
strong field QCD effect investigation in crystals allowing to observe vacuum
dichroism and birefringence, electron radiative self-polarization and polarized
electron-positron pair production by gamma-quanta, positron (electron)
anomalous magnetic moment modification and electron spin rotation in crystal
field harmonics. The effect of vacuum birefringence induced by strong electric
field is considered in detail.
