Ferroelectric Domains Engineering in 2D Van Der Waals Ferroelectric α‑In₂Se₃ Via Flexoelectric Effect

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) van der Waals ferroelectrics are crucial for next-generation nanoelectronics.
• Controlling ferroelectric polarization domains and achieving non-destructive switching are essential for device applications.
• Electric field manipulation of ultra-thin ferroelectric films is hindered by leakage currents and breakdown.

Purpose of the Study:

• To explore the flexoelectric effect for manipulating polarization states in bent alpha-Indium Selenide (α-In2Se3) flakes.
• To investigate methods for generating controllable ferroelectric polarization domains in 2D materials.

Main Methods:

• Utilized piezoresponse force microscopy (PFM) to probe ferroelectric polarization.
• Employed patterned silicon trench substrates to induce controlled bending in α-In2Se3 flakes.
• Investigated the flexoelectric effect in 2D ferroelectric materials.

Main Results:

• Observed stripe micron-scale ferroelectric domains with alternating out-of-plane polarization in curved α-In2Se3.
• Demonstrated direct reversal of polarization in the bending regions of α-In2Se3 via the flexoelectric field.
• Showcased controllable mechanical modulation of ferroelectric domains.

Conclusions:

• The flexoelectric effect offers a viable pathway for manipulating polarization states in 2D ferroelectrics.
• Controllable mechanical modulation of ferroelectric domains in α-In2Se3 opens avenues for strain engineering functional devices.
• This research advances the development of novel nanoelectronic devices based on 2D ferroelectrics.