Savytskyi A. Nonlinear electric properties of point contacts under exposure to external factors

The thesis is devoted to the study of influence of environmental factors on the behaviour of point-contact structures which are produced using the techniques of Yanson point-contact spectroscopy, meet its criteria and thus have a number of original fundamental properties. The thesis reports the results of the study of electric current states of point contacts under various conditions and communicates the obtained important information about their fundamental properties: behaviour of 2На-TaSe2/Cu heterocontacts in a medium of liquid helium was studied and the point-contact function of electron-phonon interaction, never known for this material before, was determined; some peculiarities in the electric conductance of Au/SWNT heterocontacts in a gaseous medium were found at room temperature and for the first time an extremely high sensitivity of Au/SWNT heterocontacts to trace concentrations of ammonia was observed – a change in the electric conductance amounted to about 11000%; electric current states of copper point contacts in a liquid medium were studied at room temperature and a possibility of finding the onset energy of electrochemical reaction at the atomic level in real-time mode was demonstrated.