Mechanical Manipulation of Nano-Twinned Ferroelectric Domain Structures for Multilevel Data Storage

Ferroelectric materials feature a switchable spontaneous electric polarization and can enable low-power logic and nonvolatile memories. These applications require reliable and precise control of ferroelectric domains and domain walls in ferroelectric thin films. Mechanical manipulation is a promising route to engineer ferroelectric domains, but it has proved ineffective when going beyond a critical thickness. Here, multi-step 90 degrees switching polarization reversal processes in (111)-oriented PbZr0.2Ti0.8O3 thin films by applying mechanical forces along the direction parallel to the domain bands are reported. By probing the interrelationships between the relevant order parameters, coupled lattice distortion and piezoelectricity is revealed to facilitate domain switching from downward to upward in PbZr0.2Ti0.8O3, a mechanism that is supported by the evolution of domains and electrical performances at different temperatures and under varying pressures, respectively. The multi-step domain reversal processes render PbZr0.2Ti0.8O3 thin films an excellent candidate for multilevel data storage. The study's results have implications for the manipulation of polarization switching in ferroelectrics and open an avenue to domain reversal driven by mechanical loads for the development of next-generation ferroelectric devices.

Automated summary

This study reports a method of multi-step 90 degrees polarization reversal processes in PbZr0.2Ti0.8O3 thin films by applying mechanical forces along the direction parallel to the domain bands. By probing the interrelationships between the relevant order parameters in ferroelectric materials, the coupled lattice distortion and piezoelectricity are revealed to facilitate domain switching.