Nonvolatile Memory based on Reconfigurable Ferroelectric Domain Walls

Interfaces and boundaries between competing phases and materials have gathered immense interest as potential nanoelectronic elements. IBM is currently developing ‘race-track memories’ in which the high-density digital information is encoded in the form of magnetic domain walls, which can be injected and moved controllably along 3 dimensional ferromagnetic nanowires. Only recently, analogous research in ferroelectric materials has seen tremendous interest, because of much smaller domain wall sizes and the potential of electric field induced wall movement that could enable ultralow-power electronics.
Ferroelectric domain walls are atomically-sharp topological defects that separate regions of uniform polarization. The discovery of electrical conductivity in specific types of walls gave rise to “domain wall nanoelectronics”, a technology in which the wall (rather than the domain) stores information. This paradigm shift critically hinges on precise nano-engineering of reconfigurable domain walls. Here, we demonstrate a prototype solid-state non-volatile ferroelectric domain wall memory, scalable to below 100 nm with excellent device characteristics. Our work constitutes an important step toward integrated nanoscale ferroelectric domain wall memory devices [Sci Adv 3, e1700512, 2017].