Nanoscale bubble domains with polar topologies in bulk ferroelectrics

Jie Yin; Hongxiang Zong; Hong Tao; Xuefei Tao; Haijun Wu; Yang Zhang; Li-Dong Zhao; Xiangdong Ding; Jun Sun; Jianguo Zhu; Jiagang Wu; Stephen J Pennycook

doi:10.1038/s41467-021-23863-w

Nanoscale bubble domains with polar topologies in bulk ferroelectrics

Nat Commun. 2021 Jun 15;12(1):3632. doi: 10.1038/s41467-021-23863-w.

Authors

Jie Yin^#¹, Hongxiang Zong^#², Hong Tao¹, Xuefei Tao², Haijun Wu^{3

4

5}, Yang Zhang⁶, Li-Dong Zhao⁷, Xiangdong Ding², Jun Sun², Jianguo Zhu¹, Jiagang Wu⁸, Stephen J Pennycook⁹

Affiliations

¹ Department of Materials Science, Sichuan University, Chengdu, China.
² State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China.
³ State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China. wuhaijunnavy@xjtu.edu.cn.
⁴ Department of Materials Science and Engineering, National University of Singapore, Singapore City, Singapore. wuhaijunnavy@xjtu.edu.cn.
⁵ Instrumental Analysis Center of Xi'an Jiaotong University, Xi'an Jiaotong University, Xi'an, China. wuhaijunnavy@xjtu.edu.cn.
⁶ Instrumental Analysis Center of Xi'an Jiaotong University, Xi'an Jiaotong University, Xi'an, China.
⁷ School of Materials Science and Engineering, Beihang University, Beijing, China.
⁸ Department of Materials Science, Sichuan University, Chengdu, China. msewujg@scu.edu.cn.
⁹ Department of Materials Science and Engineering, National University of Singapore, Singapore City, Singapore. stevepennycook@gmail.com.

^# Contributed equally.

Abstract

Multitudinous topological configurations spawn oases of many physical properties and phenomena in condensed-matter physics. Nano-sized ferroelectric bubble domains with various polar topologies (e.g., vortices, skyrmions) achieved in ferroelectric films present great potential for valuable physical properties. However, experimentally manipulating bubble domains has remained elusive especially in the bulk form. Here, in any bulk material, we achieve self-confined bubble domains with multiple polar topologies in bulk Bi_0.5Na_0.5TiO₃ ferroelectrics, especially skyrmions, as validated by direct Z-contrast imaging. This phenomenon is driven by the interplay of bulk, elastic and electrostatic energies of coexisting modulated phases with strong and weak spontaneous polarizations. We demonstrate reversable and tip-voltage magnitude/time-dependent donut-like domain morphology evolution towards continuously and reversibly modulated high-density nonvolatile ferroelectric memories.