Quantum conductance, known as Sharvin point contact, has been extensively investigated in many electronic devices, including diodes, transistors, and switches, especially in conductive filaments-based memristors. Quantum conductance with one or multiple atoms point connection can overcome the limitations of scaling and operating speed of nonvolatile multiple memory, logic device, and brain-inspired computing systems. However, because of the instability of the atomic arrangement in the one/multiple atoms connection in a conductive filaments-based memristor, it is a great challenge to maintain quantum conductance states for a long time. Here, we demonstrate that the stable long-time retention of multi-level quantum conductance states can be realized in Mott insulator vanadium dioxide with a highly oriented crystalline texture. According to in situ transmission electron microscope, conductive atomic force microscope, and detailed energy band analysis results, it is proposed that the grain boundaries act as reservoirs for oxygen vacancies and confine the oxygen vacancy diffusion in the narrow grain boundaries due to the higher bulk diffusion barrier. Our approach is extremely crucial for realizing quantum conductance-based electronic devices, such as multi-level and high-density storage and neuromorphic computing.

中文翻译：

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通过限制氧空位扩散实现量子电导的长保持特性

量子电导，称为 Sharvin 点接触，已在许多电子设备中得到广泛研究，包括二极管、晶体管和开关，尤其是基于导电丝的忆阻器。具有一个或多个原子点连接的量子电导可以克服非易失性多存储器、逻辑器件和类脑计算系统的缩放和运行速度的限制。然而，由于基于导电丝的忆阻器中单/多原子连接中原子排列的不稳定性，长时间保持量子电导状态是一个巨大的挑战。在这里，我们证明了在具有高度定向结晶结构的莫特绝缘体二氧化钒中可以实现多能级量子电导态的稳定长期保持。根据原位透射电子显微镜、导电原子力显微镜和详细的能带分析结果，提出晶界作为氧空位的储存库，由于更高的体积扩散，将氧空位扩散限制在窄晶界障碍。我们的方法对于实现基于量子电导的电子设备至关重要，例如多级和高密度存储以及神经形态计算。