An electric-field-driven ferroelectric nanodomain structure and its multilevel data storage application

Abstract

Solid-state multilevel data storage devices based on ferroelectric materials possess significant potential for use as artificial synapses in building biomimetic neural networks with low energy consumption and efficient data processing capabilities. To enable multilevel data storage, precise control of the ferroelectric domain through voltage pulses is essential. In this study, we investigate the manipulation of ferroelectric nanodomain structures using a nanotip and demonstrate their evolution under controlled application of electric pulses with varying strength and duration. The results highlight the differences in electric-field-driven ferroelectric nanodomain structures between (001)-/(101)- and (111)-oriented PbZr_0.2Ti_0.8O₃ thin films. Interestingly, the latter exhibits highly anisotropic domain wall motion characteristics. The (111)-oriented PbZr_0.2Ti_0.8O₃/SrRuO₃ heterostructure demonstrates the best performance in increasing the domain radius with respect to electric pulse strength and duration. It shows at least three resistance states with a high switching ratio, making it a promising candidate for multilevel data storage applications. Additionally, the self-reversal rates of upward and downward domains differ and must be considered in designing and implementing multilevel data storage systems for stability and effectiveness. These findings reveal the potential of ferroelectric nanodomain structures for data storage and pave the way for nanotip-controlled artificial synapses.