Influence of defect site transitions on discrete resistance fluctuations in normal-metal tunnel junctions

Abstract
Measurements of discrete resistance fluctuations in novel metal-insulator-metal-insulator-metal tunnel junctions show the presence of single ionic defects that can be moved reversibly between adjacent lattice sites in the insulating barrier. By analyzing the change in switching lifetimes and junction conductance resulting from these displacements, it is concluded that electron tunneling is the dominant trapping mechanism, rather than metastable transitions of the defect state.