THERMO-INDUCED SHIFT OF PLASMON ENERGY IN ELECTRON LOSS SPECTRA FOR THE ORDERING Pt 80 Co 20(111) ALLOY SURFACE

Electron energy loss spectroscopy has been used for the investigation of the surface and bulk plasmon excitations depending on the heating in the ultra-thin layers of ordering Pt 80 Co 20(111) alloy from the primary electron beam energies E0 ranging from 200 to 650 eV. Thermo-induced shift of plasmon energy and damping of intensity line of the surface plasmon relative to the bulk plasmon were observed. With an increase in alloy heating, the energy of surface and bulk plasmons is shifted with lowering energy in the whole range E0 and the higher the temperature the higher the shifts of plasmon energy. The physical processes that can influence on the energy shift of plasmon oscillations in the energy loss spectra at heating are considered. The relationship between the damping of oscillating concentration depth profile and the surface plasmon damping at heating was established.