Laboratory of multiscale materials modeling, led by Professor Shi Liu, has made progress in unraveling the mechanisms behind ferroelectric polarization switching and ion transport coupling. Their research, titled "Ultrahigh oxygen ion mobility in ferroelectric hafnia," has been published in Physical Review Letters.

In this study, Professor Liu's team employed a combination of first-principles calculations and deep neural network-based molecular dynamics to investigate the relationship between ferroelectricity and long-range oxygen ion transport in ferroelectric hafnia (HfO2). The research revealed that continuous polarization switching induced by unidirectional electric fields can drive an ion-type Thouless pumping process, enabling ultrafast oxygen ion transport at lower temperatures.

The derived concept of "ferroelectric ionics" from this work holds promise for innovative device development such as ferroelectric-electrochemical ion synapses. Additionally, based on rigorous calculations and symmetry analysis, this study provides clarification on several controversies surrounding ferroelectric hafnia, including polarization switching pathways, bivalued remnant polarization, and the sign of the piezoelectric coefficient.  

（https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.256801 ）