Departamento Física Materia Condensada, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
Phys Rev Lett. 2010 Jul 23;105(4):047207. doi: 10.1103/PhysRevLett.105.047207.
We investigate electronic transport in epitaxial Fe(100)/MgO/Fe/MgO/Fe double magnetic tunnel junctions with soft barrier breakdown (hot spots). Specificity of these junctions is continuous middle layer and nitrogen doping of the MgO barriers which provides soft breakdown at biases about 0.5 V. In the junctions with hot spots we observe quasiperiodic changes in the resistance as a function of bias voltage which point out formation of quantum well states in the middle Fe continuous free layer. The room-temperature oscillations have been observed in both parallel and antiparallel magnetic configurations and for both bias polarizations. A simple model of tunneling through hot spots in the double barrier magnetic junction is proposed to qualitatively explain this effect.
我们研究了具有软势垒击穿（热点）的外延 Fe(100)/MgO/Fe/MgO/Fe 双磁隧道结中的电子输运。这些结的特点是中间层连续和 MgO 势垒的氮掺杂，这在大约 0.5V 的偏压下提供了软击穿。在具有热点的结中，我们观察到电阻随偏压的准周期性变化，这表明在中间连续自由层 Fe 中形成了量子阱态。室温振荡在平行和反平行磁构型以及两种偏压下都有观察到。提出了一个简单的双势垒磁结中通过热点隧穿的模型，定性地解释了这一效应。
