MAGNETOQUANTUM OSCILLATIONS IN THE RESISTANCE OF METALLIC POINT CONTACTS - INFLUENCE OF NONEQUILIBRIUM PHONONS

The amplitude of magnetoresistance quantum oscillations of Al and Be p oint contacts in a magnetic field parallel to the contact axis has bee n studied as a function of voltage applied over the contact. It was fo und that for one group of contacts the oscillation amplitude nonmonoto nously increases with the bias voltage increase, while for the other p art of the contacts a decrease of amplitude was observed. The scatteri ng of electrons with nonequilibrium phonons and also phonon-phonon col lisions will be discussed as the possible reasons of the observed effe cts.