Enormous Resistance Switching Phenomena Observed In Nickel-Aluminum-Oxide Nanocomposite

摘要

We studied magnetic-transport of anodic aluminum oxide (AAO) films in which Ni was partially electrodeposited in a 50 nm diameter nanohole array. In this two-terminal device structure formed on n-Si substrate, Ta/Au electrodes were formed on the top and the bottom of AAO. We unexpectedly found a phenomenon of enormous bistable resistance switching under the in-plane magnetic field at room temperature. There are two states of high resistance and low resistance. The resistance ratio between the two states is different in each, and ranges from a few hundred % to several tens of thousand %. The switching fields distributed between 1.5 to 2.5 kOe. The reproducibility of the switching phenomenon is not good; once switching is observed, after several cycles of magneto-resistance measurement, it changes into other states with many resistance spikes or small fluctuations. This suggests that a nano-scale conduction path consisting of Ni atoms is formed under the electric field due to atomic migration, and resistance switching takes place when the magnetization of the conduction path is switched by an external field.