Polar meron lattice in strained oxide ferroelectrics

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Topological merons, half-skyrmion structures with non-coplanar order parameters, have potential for data storage.
• While merons are known in ferromagnets, their existence and behavior in ferroelectrics remain largely unexplored.

Purpose of the Study:

• To investigate the existence and formation of merons in ferroelectric materials.
• To explore the role of epitaxial strain in creating topological polar textures.

Main Methods:

• Electron microscopy was used to observe the atomic morphology of merons.
• Phase-field simulations were employed to understand meron formation mechanisms.

Main Results:

• Atomic morphology of topological merons with a charge of 1/2 was observed.
• A periodic meron lattice was identified in ultrathin PbTiO3 films under tensile epitaxial strain.
• Epitaxial strain was found to be critical in coupling lattice and charge for meron formation.

Conclusions:

• Topological merons and lattices can be formed in ferroelectric materials like PbTiO3.
• Nanoscale strain engineering is a viable method for fabricating topological polar textures.
• This research facilitates the development of advanced nanoscale ferroelectric devices.