Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré Engineering
Atomic-scale polar topologies such as skyrmions offer important potential as technological paradigms for future electronic devices. Despite recent advances in the exploration of topological domains in complicated perovskite oxide superlattices, these exotic ferroic orders are unavoidably disrupted a...
Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
American Association for the Advancement of Science (AAAS)
2025-01-01
|
| Series: | Research |
| Online Access: | https://spj.science.org/doi/10.34133/research.0621 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849325377458012160 |
|---|---|
| author | Tao Xu Tao Qian Jiafei Pang Jingtong Zhang Sheng Li Ri He Jie Wang Takahiro Shimada |
| author_facet | Tao Xu Tao Qian Jiafei Pang Jingtong Zhang Sheng Li Ri He Jie Wang Takahiro Shimada |
| author_sort | Tao Xu |
| collection | DOAJ |
| description | Atomic-scale polar topologies such as skyrmions offer important potential as technological paradigms for future electronic devices. Despite recent advances in the exploration of topological domains in complicated perovskite oxide superlattices, these exotic ferroic orders are unavoidably disrupted at the atomic scale due to intrinsic size effects. Here, based on first-principles calculations, we propose a new strategy to design robust ferroelectricity in atomically thin films by properly twisting 2 monolayers of centrosymmetric SrTiO3. Surprisingly, the emerged polarization vectors curl in the plane, forming a polar skyrmion lattice with each skyrmion as small as 1 nm, representing the highest polar skyrmion density to date. The emergent ferroelectricity originates from strong interlayer coupling effects and the resulting unique strain fields with obvious ion displacements, contributing to electric polarization comparable to that of PbTiO3. Moreover, we observe ultraflat bands (band width of less than 5 meV) at the valence band edge across a wide range of twist angles, which show widths that are smaller than those of common twisted bilayers of 2-dimensional materials. The present study not only overcomes the critical size limitation for ferroelectricity but also reveals a novel approach for achieving atomic-scale polar topologies, with important potential for applications in skyrmion-based ultrahigh-density memory technologies. |
| format | Article |
| id | doaj-art-e4829d12250c4e8cb0479bae0447c362 |
| institution | Kabale University |
| issn | 2639-5274 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | American Association for the Advancement of Science (AAAS) |
| record_format | Article |
| series | Research |
| spelling | doaj-art-e4829d12250c4e8cb0479bae0447c3622025-08-20T03:48:26ZengAmerican Association for the Advancement of Science (AAAS)Research2639-52742025-01-01810.34133/research.0621Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré EngineeringTao Xu0Tao Qian1Jiafei Pang2Jingtong Zhang3Sheng Li4Ri He5Jie Wang6Takahiro Shimada7Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan.Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan.Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, China.Department of Civil and Earth Resources Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan.Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, China.Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan.Atomic-scale polar topologies such as skyrmions offer important potential as technological paradigms for future electronic devices. Despite recent advances in the exploration of topological domains in complicated perovskite oxide superlattices, these exotic ferroic orders are unavoidably disrupted at the atomic scale due to intrinsic size effects. Here, based on first-principles calculations, we propose a new strategy to design robust ferroelectricity in atomically thin films by properly twisting 2 monolayers of centrosymmetric SrTiO3. Surprisingly, the emerged polarization vectors curl in the plane, forming a polar skyrmion lattice with each skyrmion as small as 1 nm, representing the highest polar skyrmion density to date. The emergent ferroelectricity originates from strong interlayer coupling effects and the resulting unique strain fields with obvious ion displacements, contributing to electric polarization comparable to that of PbTiO3. Moreover, we observe ultraflat bands (band width of less than 5 meV) at the valence band edge across a wide range of twist angles, which show widths that are smaller than those of common twisted bilayers of 2-dimensional materials. The present study not only overcomes the critical size limitation for ferroelectricity but also reveals a novel approach for achieving atomic-scale polar topologies, with important potential for applications in skyrmion-based ultrahigh-density memory technologies.https://spj.science.org/doi/10.34133/research.0621 |
| spellingShingle | Tao Xu Tao Qian Jiafei Pang Jingtong Zhang Sheng Li Ri He Jie Wang Takahiro Shimada Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré Engineering Research |
| title | Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré Engineering |
| title_full | Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré Engineering |
| title_fullStr | Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré Engineering |
| title_full_unstemmed | Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré Engineering |
| title_short | Creating Ferroelectricity and Ultrahigh-Density Polar Skyrmion in Paraelectric Perovskite Oxide Monolayers by Moiré Engineering |
| title_sort | creating ferroelectricity and ultrahigh density polar skyrmion in paraelectric perovskite oxide monolayers by moire engineering |
| url | https://spj.science.org/doi/10.34133/research.0621 |
| work_keys_str_mv | AT taoxu creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering AT taoqian creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering AT jiafeipang creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering AT jingtongzhang creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering AT shengli creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering AT rihe creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering AT jiewang creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering AT takahiroshimada creatingferroelectricityandultrahighdensitypolarskyrmioninparaelectricperovskiteoxidemonolayersbymoireengineering |