The peculiar features of domain walls observed in ferroelectrics make them promising active elements for next-generation non-volatile memories, logic gates and energy-harvesting devices. Although extensive research activity has been devoted recently to making full use of this technological potential, concrete realizations of working nanodevices exploiting these functional properties are yet to be demonstrated. Here, we fabricate a multiferroic tunnel junction based on ferromagnetic La_0.7Sr_0.3MnO₃ electrodes separated by an ultrathin ferroelectric BaTiO₃ tunnel barrier, where a head-to-head domain wall is constrained. An electron gas stabilized by oxygen vacancies is confined within the domain wall, displaying discrete quantum-well energy levels. These states assist resonant electron tunnelling processes across the barrier, leading to strong quantum oscillations of the electrical conductance.

中文翻译：

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多铁性隧道结中带电畴壁辅助的共振电子隧穿

铁电体中观察到的畴壁的独特特征使其成为下一代非易失性存储器，逻辑门和能量收集设备的有希望的有源元件。尽管最近已经进行了广泛的研究活动，以充分利用这种技术潜力，但是，利用这些功能特性的工作纳米器件的具体实现尚待证明。在这里，我们基于由超薄铁电BaTiO ₃隔开的铁磁La _0.7 Sr _0.3 MnO ₃电极制造了多铁性隧道结隧道屏障，其中头对头畴壁受到约束。通过氧空位稳定的电子气被限制在畴壁内，显示出离散的量子阱能级。这些状态有助于跨势垒的共振电子隧穿过程，从而导致电导的强量子振荡。