Abstract
We demonstrated that the formation of magnetic conductive filaments in Co/ZnO/Fe sandwich structures can be employed to produce a nanoscale magnetic tunnel junction (MTJ) and control the tunneling magnetoresistance (TMR). The pristine Co/ZnO/Fe structures with a 100nm thick ZnO layer do not exhibit any remarkable TMR. Under voltage sweeps performed on the sandwich devices, Co conductive filaments were grown in a ZnO layer, which leads to the formation of nanoscale Co/ZnO/Fe MTJs and the occurrence of TMR. In addition, a sign inversion of TMR was found in the nano-MTJs by carrying out the further voltage sweeps or varying the measuring bias voltage, which could be well understood in terms of the resonant tunneling caused by impurity scattering in a ZnO barrier.
| Original language | English |
|---|---|
| Article number | 58004 |
| Journal | Europhysics Letters |
| Volume | 108 |
| Issue number | 5 |
| DOIs | |
| State | Published - 1 Dec 2014 |
| Externally published | Yes |