In many-body nonlinear systems with sufficient anharmonicity, a special kind of localized lattice oscillations, namely,
discrete breathers (DB) can be excited, in which the amplitude of atomic oscillations greatly exceeds that of harmonic
oscillations (phonons). The coherency and persistence of DB may have strong effect on quantum tunneling due to
correlation effects discovered by Schrödinger and Robertson in 1930. These effects have been applied to the tunneling
problem by some authors, who demonstrated a strong increase of sub-barrier transparency during increase of the correlation
coefficient. We show that DB present a natural way to produce correlation effects