Gyrosolitons and helical surfing diffusion of impurity atoms in reactor fuel materials

Fundamentally new gyrosolitons with helical trajectories of motion have been revealed in UO$_2$ and PuO$_2$ reactor fuel materials by the computer simulation of the microdynamics of high-amplitude atomic vibrations. The phonon spectra of nanostructures, as well as of gyrotropic materials, include quasioptical branches with different-sign linear dispersion. The corresponding branches of gyrosolitons have been revealed on the phase plane in the spectral density of vibrations. The main dynamic event of the kinetic process of helical surfing diffusion of impurity atoms on gyrosolitons has been observed.