2024/08/09 by Kunihiko Yamauchi, Yamauchi, Kunihiko, Thi Phuong Thao Nguyen +3
Materials Science · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Nonlocal and gradient elasticity in micro/nano structures
paper · pdf · doi:10.48550/arxiv.2408.04985
openalex publication_date 2024/08/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Flexoelectricity refers to a linear coupling between the electric polarization and the strain gradient, such as bending or asymmetric compression. This effect is enhanced in nano-scale structures, where grain boundaries or dislocation cores induce the strain gradient. In this study, we theoretically investigate the flexoelectric polarization induced by misfit dislocations in a thin film. A nano-scale dislocation structure is modeled in a periodic SrTiO3 supercell, and then the structure is optimized by using neural-network-potential and first-principles approaches. We point out that a pyramidal TiO5 coordination forms near the dislocation cores, which in turn dominantly causes the sizable flexoelectric polarization.