Saved in:
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2511.01241 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866911412734918656 |
|---|---|
| author | Yoshida, Suguru Hernandez, Olivier Miyake, Jinsuke Nakayama, Kei Ishikawa, Ryo Hojo, Hajime Ikuhara, Yuichi Gopalan, Venkatraman Tanaka, Katsuhisa Fujita, Koji |
| author_facet | Yoshida, Suguru Hernandez, Olivier Miyake, Jinsuke Nakayama, Kei Ishikawa, Ryo Hojo, Hajime Ikuhara, Yuichi Gopalan, Venkatraman Tanaka, Katsuhisa Fujita, Koji |
| contents | While defects are unavoidable in crystals and often detrimental to material performance, they can be a key ingredient for inducing functionalities when tailored. Here, we demonstrate that an A-site-deficient perovskite Y$_{1/3}$TaO$_3$ exhibits room-temperature ferroelectricity in a $Pb2_1m$ phase, enabled by ordered vacancies coupled with TaO$_6$ octahedral rotations. Defect-ordered perovskites are frequently trapped in centrosymmetric incommensurate states due to competing structural instabilities; we circumvent this by favoring rotational over polar instability through compositional selection. Unlike canonical improper ferroelectrics that are \textit{ferrielectric}, the vanishing dipoles on vacancy layers in Y$_{1/3}$TaO$_3$ allow for a net ferroelectric alignment of local dipoles, resulting in enhanced polarization. Upon heating, Y$_{1/3}$TaO$_3$ transforms to a paraelectric incommensurate phase at $\simeq$750 K, whose atomic arrangement mirrors the domain topology observed in hybrid improper ferroelectrics. Superspace analysis of the modulated phase reveals a route to improve room-temperature polarization, achieved through epitaxial strain, as confirmed by our lattice-dynamics calculations. This defect-ordering strategy should be generalizable to other improper ferroelectrics, including magnetoelectric multiferroics, providing a pathway to amplify otherwise limited macroscopic polarization. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2511_01241 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Switchable Polarization in an A-site Deficient Perovskite through Vacancy and Cation Engineering Yoshida, Suguru Hernandez, Olivier Miyake, Jinsuke Nakayama, Kei Ishikawa, Ryo Hojo, Hajime Ikuhara, Yuichi Gopalan, Venkatraman Tanaka, Katsuhisa Fujita, Koji Materials Science While defects are unavoidable in crystals and often detrimental to material performance, they can be a key ingredient for inducing functionalities when tailored. Here, we demonstrate that an A-site-deficient perovskite Y$_{1/3}$TaO$_3$ exhibits room-temperature ferroelectricity in a $Pb2_1m$ phase, enabled by ordered vacancies coupled with TaO$_6$ octahedral rotations. Defect-ordered perovskites are frequently trapped in centrosymmetric incommensurate states due to competing structural instabilities; we circumvent this by favoring rotational over polar instability through compositional selection. Unlike canonical improper ferroelectrics that are \textit{ferrielectric}, the vanishing dipoles on vacancy layers in Y$_{1/3}$TaO$_3$ allow for a net ferroelectric alignment of local dipoles, resulting in enhanced polarization. Upon heating, Y$_{1/3}$TaO$_3$ transforms to a paraelectric incommensurate phase at $\simeq$750 K, whose atomic arrangement mirrors the domain topology observed in hybrid improper ferroelectrics. Superspace analysis of the modulated phase reveals a route to improve room-temperature polarization, achieved through epitaxial strain, as confirmed by our lattice-dynamics calculations. This defect-ordering strategy should be generalizable to other improper ferroelectrics, including magnetoelectric multiferroics, providing a pathway to amplify otherwise limited macroscopic polarization. |
| title | Switchable Polarization in an A-site Deficient Perovskite through Vacancy and Cation Engineering |
| topic | Materials Science |
| url | https://arxiv.org/abs/2511.01241 |