Topological Phase Transitions, Phase Diagrams, and Dielectric Properties of Pb(Zr0.7Ti0.3)O3‐Based Superlattices

• Published in: Advanced Physics Research Vol. 4; no. 8
• Main Authors: Chen, Zhouping, Huang, Yuhui, Wu, Yongjun, Li, Juan, Hong, Zijian
• Format: Journal Article
• Language: English
• Published: Wiley-VCH 01.08.2025
• Subjects: dielectric responses; phase‐field simulations; polar topologies; PZT
• ISSN: 2751-1200; 2751-1200
• DOI: 10.1002/apxr.202500004

Ferroelectric/paraelectric superlattices, created through the periodic stacking of their constituent materials, exhibit intricate phase diagrams that reveal a variety of polar topologies and properties not found in any of the individual components. In this study, the phase‐field simulations are utilized to systematically calculate the phase diagrams of Zr‐rich Pb(Zr, Ti)O3/SrTiO3 superlattices with varying periodicity, strain, and temperature. A rhombohedral‐type labyrinth domain is observed, which is oriented along the [110] direction under relatively low compressive strain. Meanwhile, higher compressive strains lead to the formation of polar skyrmions with shorter periodicities. Notably, a high dielectric permittivity of 1700 is found at room temperature for the polar skyrmion phase with a periodicity of 6 when grown on a DyScO3 substrate, which is double the value for the skyrmion phase in a PbTiO3/SrTiO3 superlattice. Moreover, a phase transition from skyrmion, vortex/labyrinth states to a cubic phase at elevated temperatures is discovered, accompanied by a significant reduction in dielectric responses. It is hoped that the work will inspire further exploration into the design of intriguing polar topologies with superior properties. The phase‐field simulations are used to systematically calculate the phase diagrams of PZT/STO superlattices, considering various periodicities, strains, and temperatures. A rhombohedral‐type labyrinth domain oriented along the [110] direction is observed under low compressive strain. The dielectric responses for different polar topologies are examined, and a high dielectric permittivity of 1700 is discovered, associated with the negative capacitance in polar skyrmion phase.