Light emission from small copper particles excited by current passage or by low-energy electron bombardment

The light emission from small Cu particles was investigated by passing electrical current through them as well as during bombardment by low-energy electrons (less than or equal to 400 eV). Measurements were performed in the spectral range 1.18-6.2 eV. The shape of the spectra was dependent on the voltage applied to the tunnel-coupled small Cu particles. As the voltage increases, some features arise in the high-energy part of the spectra. For different modes of particles' excitation spectra differ in peaks intensities, but their position on the energy scale remains constant. Thus, a conclusion can be drawn that the nature of the light emission obtained at various excitation modes is caused by similar physical origins. (C) 2001 Elsevier Science B.V. All rights reserved.