Uvarova I. Physical properties of carbon nanotubes irradiated in various gas media.

The thesis is devoted to experimental and theoretical investigations of ? irradiation in various gas media effect on electrical, sorption and desorption properties of single-walled carbon nanotube bundles. It is shown, both theoretically and experimentally, that surrounding gas atoms are directly involved into irradiation defects introduction process. Furthermore, the irradiation defect introduction efficiency into single-walled carbon nanotube bundles non-monotonically depends on the atomic mass of the gas medium. It was found that the electrical conductivity of single-walled carbon nanotube bundles, alike single nanotubes, is in Tomonaga Luttinger liquid state, which is common for strongly correlated quasi-one dimensional electron subsystems. Radiation stability of the Tomonaga Luttinger liquid state in carbon nanotube bundles was observed up to doses 1.2х108 rad in vacuum, hydrogen and deuterium media in temperature range from 25 to 300 K. Experimental investigation and theoretical analysis confirm the quantum nature of light gas atoms (isotopes of hydrogen and helium) outflow from single-walled carbon nanotube bundles at low temperatures. The activation energies and the crossover temperatures (from classical thermo-activation outflow regime to tunneling) were established experimentally. The character of crossover temperature dependence on gas atomic mass agrees with the tunneling within strong dissipation regime and indicates on the strong interaction between moving gas atoms and phonon subsystem of carbon nanotubes.