Engineering Domain Variants in 0.7Pb(Mg_1/3Nb_2/3)-0.3PbTiO₃ Single Crystals Using High-Frequency AC Poling

Area of Science:

• Materials Science
• Solid State Physics
• Crystallography

Background:

• Single crystals of 0.7Pb(Mg1/3Nb2/3)-0.3PbTiO3 (PMN-30PT) exhibit excellent dielectric and electromechanical properties near the morphotropic phase boundary.
• Alternating current (AC) electric field poling enhances these properties, but the underlying domain dynamics under high frequencies are not well understood.

Purpose of the Study:

• To investigate the microscopic domain structure and dynamics in PMN-30PT crystals under high-frequency AC poling.
• To understand the role of domain variants and domain walls in material performance under AC electric fields.

Main Methods:

• Utilized a combination of scanning probe microscopy and X-ray diffraction (XRD) reciprocal space mapping.
• Employed time-resolved Kelvin probe force microscopy (KPFM) to study charge dynamics.

Main Results:

• Identified four monoclinic (MA) domain variants under AC poling.
• Observed the emergence of hierarchical fine domains, specifically needle-shaped domains and 109° domain walls.
• KPFM revealed charge dynamics and relaxation behavior within these needle domains and walls.

Conclusions:

• High-frequency AC poling induces a unique domain microstructure in PMN-30PT crystals.
• The findings offer insights into domain engineering for advanced transducer applications.