Jiang Xingan, Zhang Xiangping, Deng Zunyi, Deng Jianming, Wang Xiaolei, Wang Xueyun, Yang Weiyou
Institute of Micro/Nano Materials and Devices, Ningbo University of Technology, Ningbo, China.
Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, China.
Nat Commun. 2024 Dec 30;15(1):10822. doi: 10.1038/s41467-024-55160-7.
Due to its "ferroionic" nature, CuInPS combines switchable ferroelectric polarization with highly mobile Cu ions, allowing for multiple resistance states. Its conductive mechanism involves ferroelectric switching, ion migration, and corresponding intercoupling, which are highly sensitive to external electric field. Distinguishing the dominant contribution of either ferroelectric switching or ion migration to dynamic conductivity remains a challenge and the conductive mechanism is not clear yet. Here, based on polarization switching analyses and first-principles calculations, this work demonstrates that the Cu ion migration pathways enable the formation of a quadruple-well state, determining the conductive mechanism. Accordingly, it favors the manipulation of Cu ion transport in the intralayer and interlayer in a controlled manner, and makes a transition from ferroelectric-dominated to ion-migration-dominated conductivity, by tailoring the electric fields. This work deepens the understanding of ion migration dynamics and conductive switching in ferroionic systems, which is critical for the advancement of memristor-based neuromorphic computing.
由于其“铁离子性”本质，CuInPS将可切换的铁电极化与高迁移率的铜离子相结合，从而实现多种电阻状态。其导电机制涉及铁电开关、离子迁移以及相应的相互耦合，这些对外部电场高度敏感。区分铁电开关或离子迁移对动态电导率的主要贡献仍然是一个挑战，并且导电机制尚不清楚。在此，基于极化开关分析和第一性原理计算，这项工作表明铜离子迁移路径能够形成四阱态，从而决定了导电机制。因此，通过调整电场，它有利于以可控方式操纵层内和层间的铜离子传输，并实现从铁电主导到离子迁移主导的电导率转变。这项工作加深了对铁离子系统中离子迁移动力学和导电开关的理解，这对于基于忆阻器的神经形态计算的发展至关重要。
