Memory effect and negative differential resistance by electrode-induced two-dimensional single-electron tunneling in molecular and organic electronic devices

Mysterious negative differential resistances and memory effects are commonly observed in molecular electronic thin-film devices such as organic light-emitting diodes. The authors describe how this may result from the formation of metallic nanospheres (see Figure) inside crevices resulting from defects, such as dust particles. Single-electron tunneling between the nanospheres, which are formed by nucleation and growth processes at the defect sites, results in the observed anomalous effects.