Oxygen vacancy is one of the pivotal factors for tuning/creating various oxide properties. Understanding the behavior of oxygen vacancies is of paramount importance. In this study, we identify a metastable oxygen vacancy ordering state other than the well-known Magnéli phases in TiO₂ crystals from both experimental and theoretical studies. The oxygen vacancy ordering is found to be a zigzag chain along the [001] direction in the (110) plane occurring in a wide temperature range of 200 to 500 ^oC. This metastable ordering state leads to a first-order phase transition accompanied by significant enhancement of dielectric permittivity and a memristive effect featuring a low driving electric field. Our results can improve oxide properties by engineering oxygen vacancies.

氧空位是调节/产生各种氧化物特性的关键因素之一。了解氧空位的行为至关重要。在这项研究中，我们从实验和理论研究中确定了 TiO ₂晶体中不同于众所周知的 Magnéli 相的亚稳氧空位有序状态。^{在 200 至 500 o} C的宽温度范围内，发现氧空位有序是沿 (110) 平面中 [001] 方向的锯齿形链。这种亚稳态有序状态导致一阶相变伴随着介电常数的显着增强和具有低驱动电场的忆阻效应。我们的结果可以通过设计氧空位来改善氧化物性能。