Broken inversion symmetry in van der Waals topological ferromagnetic metal iron germanium telluride
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2023
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866917886820352000 |
|---|---|
| author | Zhang, Kai-Xuan Ju, Hwiin Kim, Hyuncheol Cui, Jingyuan Keum, Jihoon Park, Je-Geun Lee, Jong Seok |
| author_facet | Zhang, Kai-Xuan Ju, Hwiin Kim, Hyuncheol Cui, Jingyuan Keum, Jihoon Park, Je-Geun Lee, Jong Seok |
| contents | Inversion symmetry breaking is critical for many quantum effects and fundamental for spin-orbit torque, which is crucial for next-generation spintronics. Recently, a novel type of gigantic intrinsic spin-orbit torque has been established in the topological van-der-Waals (vdW) magnet iron germanium telluride. However, it remains a puzzle because no clear evidence exists for interlayer inversion symmetry breaking. Here, we report the definitive evidence of broken inversion symmetry in iron germanium telluride directly measured by the second harmonic generation (SHG) technique. Our data show that the crystal symmetry reduces from centrosymmetric P63/mmc to noncentrosymmetric polar P3m1 space group, giving the three-fold SHG pattern with dominant out-of-plane polarization. Additionally, the SHG response evolves from an isotropic pattern to a sharp three-fold symmetry upon increasing Fe deficiency, mainly due to the transition from random defects to ordered Fe vacancies. Such SHG response is robust against temperature, ensuring unaltered crystalline symmetries above and below the ferromagnetic transition temperature. These findings add crucial new information to our understanding of this interesting vdW metal, iron germanium telluride: band topology, intrinsic spin-orbit torque and topological vdW polar metal states. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2312_14384 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Broken inversion symmetry in van der Waals topological ferromagnetic metal iron germanium telluride Zhang, Kai-Xuan Ju, Hwiin Kim, Hyuncheol Cui, Jingyuan Keum, Jihoon Park, Je-Geun Lee, Jong Seok Materials Science Applied Physics Optics Quantum Physics Inversion symmetry breaking is critical for many quantum effects and fundamental for spin-orbit torque, which is crucial for next-generation spintronics. Recently, a novel type of gigantic intrinsic spin-orbit torque has been established in the topological van-der-Waals (vdW) magnet iron germanium telluride. However, it remains a puzzle because no clear evidence exists for interlayer inversion symmetry breaking. Here, we report the definitive evidence of broken inversion symmetry in iron germanium telluride directly measured by the second harmonic generation (SHG) technique. Our data show that the crystal symmetry reduces from centrosymmetric P63/mmc to noncentrosymmetric polar P3m1 space group, giving the three-fold SHG pattern with dominant out-of-plane polarization. Additionally, the SHG response evolves from an isotropic pattern to a sharp three-fold symmetry upon increasing Fe deficiency, mainly due to the transition from random defects to ordered Fe vacancies. Such SHG response is robust against temperature, ensuring unaltered crystalline symmetries above and below the ferromagnetic transition temperature. These findings add crucial new information to our understanding of this interesting vdW metal, iron germanium telluride: band topology, intrinsic spin-orbit torque and topological vdW polar metal states. |
| title | Broken inversion symmetry in van der Waals topological ferromagnetic metal iron germanium telluride |
| topic | Materials Science Applied Physics Optics Quantum Physics |
| url | https://arxiv.org/abs/2312.14384 |