Manipulating ferroelectric domains in nanostructures under electron beams

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Freestanding barium titanate (BaTiO3) nanodots display unique ferroelastic 90° domain structures.
• Observed domain patterns in transmission electron microscopy (TEM) contrast with those seen in piezoresponse force microscopy (PFM).

Purpose of the Study:

• To investigate the discrepancy between TEM and PFM observations of BaTiO3 nanodot domain structures.
• To elucidate the role of electron beam charging in altering ferroelectric domain configurations.

Main Methods:

• Phase field simulations were employed to model BaTiO3 nanodot behavior.
• Simulations analyzed the impact of radial electric fields induced by electron beam charging.

Main Results:

• TEM observations of quadrant domain patterns are attributed to electron beam-induced radial electric fields.
• Sufficient charging converts flux-closure domain patterns into quadrant patterns with radial net polarization.

Conclusions:

• Electron beam charging is a key factor explaining observed TEM domain patterns in BaTiO3 nanodots.
• This finding offers a method to manipulate ferroelectric domain structures using electron beams.