β-angle Distortion Stabilized Antiferroelectricity in Engineered ZrO₂-LSMO Laminate Structure

Area of Science:

• Materials Science
• Solid State Physics
• Thin Film Technology

Background:

• Fluorite-structured thin films are crucial for ferro-/anti-ferroelectric applications due to their CMOS compatibility.
• Stabilizing antiferroelectricity in epitaxial fluorites is a significant challenge, hindering fundamental understanding and device development.

Purpose of the Study:

• To stabilize the antiferroelectric Pbca phase in ZrO2-LSMO laminate structures.
• To investigate the role of lattice distortions in stabilizing antiferroelectricity.
• To establish a phase stability map for ZrO2 epitaxial films.

Main Methods:

• Growth of ZrO2-LSMO laminate structures on LSAT (110) substrates.
• Analysis of lattice distortions using experimental techniques and density functional theory (DFT).
• Development of a phase stability map for ZrO2 epitaxial films under various strain conditions.

Main Results:

• Successful stabilization of the antiferroelectric Pbca phase in ZrO2-LSMO films.
• Demonstration of a reversible and non-volatile phase transition between Pbca and Pca21 phases.
• Identification of β-angle distortion as the critical factor for stabilizing the Pbca phase and governing its transition.

Conclusions:

• Epitaxial interfaces with controlled dislocations can stabilize antiferroelectricity in fluorite systems.
• β-angle distortion is a tunable parameter for designing antiferroelectric properties in ZrO2 films.
• This work opens new avenues for optimizing fluorite oxide-based information and energy storage devices.