Effect of the energy transfer collision between noble gas and sputtered metal atom on the voltage-current curve of a hollow-cathode discharge

The voltage-current curves and the optogalvanic signals of hollow-cathode d ischrge tubes were measured. Attention was focused on the existence of nega tive dynamic resistance properties for argon and neon discharges. Three hol low-cathodes, each was made of gadolinium, uranium, and copper, were used w ith both the noble gases. The negative dynamic resistance regions were obse rved only in Ar/U, Ar/Gd, and Ne/Cu discharges. These results suggest that resonant Penning ionization is one of the main reactions producing the nega tive dynamic resistance characteristics in hollow-cathode discharges.