RELAXATION AND RECOMBINATION CHANNELS OF FORMATION OF LUMINESCENT STATES IN A NEON CRYSTAL - EVIDENCE OF ELECTRON SELF-TRAPPING

The relation between the temperature and the intensity distribution in luminescence bands in VUV and VIS spectral regions of Ne crystals is investigated. The measurements are made by using cathodoluminescent sp ectroscopy with steady-state excitation and are supplemented by observ ations of luminescence decay in perfect pure crystals, in samples with defects, and in solid solutions with electronegative (oxygen) and ele ctropositive (xenon) impurities. The contribution of the recombination channel to the formation of the spectrum of self-trapped states in so lid neon is determined. It is shown that this channel plays a decisive role in the population of 3p(3p') luminescence centers and makes a re latively small contribution to the population of the lowermost 3s(3s') excitations. The recombination channel efficiency strongly depends on temperature, increasing abruptly with the temperature value. An analy sis of experimental data leads to the conclusion on the possibility of electron self-trapping in Ne cryocrystals, followed by the formation of shallow self-trapped states. (C) 1997 American institute of Physics .