2026/04/30 by Shibo Fang, Jianhua Wang, Zhenzhou Guo +7 · 1 citation
Physics and Astronomy · #cond-mat.mtrl-sci
This replacement retains the central concept of the previous version but substantially revises the examples, theoretical framework, and overall presentation. Although the new version differs considerably from the earlier manuscript, we chose to replace the arXiv submission to avoid confusion regarding the concept and its terminology
arxiv created 2026/08/05 · arxiv updated 2026/08/06
Ferroelectric switching provides a nonvolatile way to control electronic structures, but a general symmetry rule connecting the full Bloch bands of two switchable polarization states is still lacking. Here, we introduce ferroelectric band twinning, a pair-state relation in which the bands of two opposite-polarization states are mapped onto each other by a non-inversion state-exchange symmetry. Using dichromatic groups, we derive the band-twinning rule and identify 11 ferroelectric band-twinning point-group classes. Screening the Ferroelectric Materials Database yields 16 candidate compounds, of which the two lattice-metric-preserving candidates, bulk gamma-Ag3SI and BaAl2O4, are selected for first-principles validation. For gamma-Ag3SI, we further show that the same pair-state symmetry controls the transformation of shift-current tensor components under polarization reversal. These results establish ferroelectric band twinning as a general symmetry framework for nonvolatile control of momentum-dependent electronic structures in ferroelectrics.