Electric-field-induced submicrosecond resistive switching
Electric-ﬁeld-induced resistive switching in metal-oxide interfaces has attracted extensive recent interest. While many agree that lattice defects play a key role, details of the physical processes are far from clear. There is debate, for example, regarding whether the electromigration of pre-existing point defects or the ﬁeld-created larger lattice defects dominates the switch. We investigate several Ag-Pr0.7Ca0.3MnO3 samples exhibiting either submicrosecond fast switching or slow quasistatic dc switching. It is found that the carrier trapping potentials are very different for the pre-existing point defects associated with doping ͑and/or electromigration͒ and for the defects responsible for the submicrosecond fast switching. Creation/removal of the defects with more severe lattice distortions and spatial spreading ͑trapping potential Ն0.35 eV͒, therefore, should be the dominating mechanism during submicrosecond switching. On the other hand, the shallow defects ͑trapping potential Ӷ0.2 eV͒ associated with doping/annealing are most likely responsible for the resistance hysteresis ͑slow switch͒ during quasistatic voltage sweep.