Utilizing quantum effects in complex oxides, such as magnetism, multiferroicity and superconductivity, requires atomic-level control of the material’s structure and composition. In contrast, the continuous conductivity changes that enable artificial oxide-based synapses and multiconfigurational devices are driven by redox reactions and domain reconfigurations, which entail long-range ionic migration and changes in stoichiometry or structure. Although both concepts hold great technological potential, combined applications seem difficult due to the mutually exclusive requirements. Here we demonstrate a route to overcome this limitation by controlling the conductivity in the functional oxide hexagonal Er(Mn,Ti)O₃ by using conductive atomic force microscopy to generate electric-field induced anti-Frenkel defects, that is, charge-neutral interstitial–vacancy pairs. These defects are generated with nanoscale spatial precision to locally enhance the electronic hopping conductivity by orders of magnitude without disturbing the ferroelectric order. We explain the non-volatile effects using density functional theory and discuss its universality, suggesting an alternative dimension to functional oxides and the development of multifunctional devices for next-generation nanotechnology.

利用复杂氧化物中的量子效应，例如磁性，多铁性和超导性，需要对材料的结构和组成进行原子级控制。相比之下，氧化还原反应和域重配置驱动着能够进行基于人工氧化物的突触和多构型装置的连续电导率变化，这需要长距离离子迁移以及化学计量或结构变化。尽管这两个概念都具有巨大的技术潜力，但由于相互排斥的要求，组合应用似乎很困难。在这里，我们展示了通过控制功能性氧化物六角形Er（Mn，Ti）O _3中的电导率来克服此限制的途径通过使用导电原子力显微镜产生电场感应的反弗伦克尔缺陷，即电荷中性间隙-空位对。这些缺陷的产生具有纳米级的空间精度，可以在不干扰铁电有序的情况下将电子跳跃电导率局部提高几个数量级。我们使用密度泛函理论解释了非易失性效应，并讨论了其普遍性，为功能性氧化物提出了另一种选择，并为下一代纳米技术开发了多功能器件。