Direct observation of topological magnon polarons in a multiferroic material
Abstract Magnon polarons are novel elementary excitations possessing hybrid magnonic and phononic signatures, and are responsible for many exotic spintronic and magnonic phenomena. Despite long-term sustained experimental efforts in chasing for magnon polarons, direct spectroscopic evidence of their...
| Main Authors: | , , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2023-09-01
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| Series: | Nature Communications |
| Online Access: | https://doi.org/10.1038/s41467-023-41791-9 |
| _version_ | 1797558226264260608 |
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| author | Song Bao Zhao-Long Gu Yanyan Shangguan Zhentao Huang Junbo Liao Xiaoxue Zhao Bo Zhang Zhao-Yang Dong Wei Wang Ryoichi Kajimoto Mitsutaka Nakamura Tom Fennell Shun-Li Yu Jian-Xin Li Jinsheng Wen |
| author_facet | Song Bao Zhao-Long Gu Yanyan Shangguan Zhentao Huang Junbo Liao Xiaoxue Zhao Bo Zhang Zhao-Yang Dong Wei Wang Ryoichi Kajimoto Mitsutaka Nakamura Tom Fennell Shun-Li Yu Jian-Xin Li Jinsheng Wen |
| author_sort | Song Bao |
| collection | DOAJ |
| description | Abstract Magnon polarons are novel elementary excitations possessing hybrid magnonic and phononic signatures, and are responsible for many exotic spintronic and magnonic phenomena. Despite long-term sustained experimental efforts in chasing for magnon polarons, direct spectroscopic evidence of their existence is hardly observed. Here, we report the direct observation of magnon polarons using neutron spectroscopy on a multiferroic Fe2Mo3O8 possessing strong magnon-phonon coupling. Specifically, below the magnetic ordering temperature, a gap opens at the nominal intersection of the original magnon and phonon bands, leading to two separated magnon-polaron bands. Each of the bands undergoes mixing, interconverting and reversing between its magnonic and phononic components. We attribute the formation of magnon polarons to the strong magnon-phonon coupling induced by Dzyaloshinskii-Moriya interaction. Intriguingly, we find that the band-inverted magnon polarons are topologically nontrivial. These results uncover exotic elementary excitations arising from the magnon-phonon coupling, and offer a new route to topological states by considering hybridizations between different types of fundamental excitations. |
| first_indexed | 2024-03-10T17:28:21Z |
| format | Article |
| id | doaj.art-5af7db7a8f58480b96c6e6bbfb85a49e |
| institution | Directory Open Access Journal |
| issn | 2041-1723 |
| language | English |
| last_indexed | 2024-03-10T17:28:21Z |
| publishDate | 2023-09-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Nature Communications |
| spelling | doaj.art-5af7db7a8f58480b96c6e6bbfb85a49e2023-11-20T10:06:42ZengNature PortfolioNature Communications2041-17232023-09-011411910.1038/s41467-023-41791-9Direct observation of topological magnon polarons in a multiferroic materialSong Bao0Zhao-Long Gu1Yanyan Shangguan2Zhentao Huang3Junbo Liao4Xiaoxue Zhao5Bo Zhang6Zhao-Yang Dong7Wei Wang8Ryoichi Kajimoto9Mitsutaka Nakamura10Tom Fennell11Shun-Li Yu12Jian-Xin Li13Jinsheng Wen14National Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityDepartment of Applied Physics, Nanjing University of Science and TechnologySchool of Science, Nanjing University of Posts and TelecommunicationsJ-PARC Center, Japan Atomic Energy Agency (JAEA)J-PARC Center, Japan Atomic Energy Agency (JAEA)Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute (PSI)National Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityNational Laboratory of Solid State Microstructures and Department of Physics, Nanjing UniversityAbstract Magnon polarons are novel elementary excitations possessing hybrid magnonic and phononic signatures, and are responsible for many exotic spintronic and magnonic phenomena. Despite long-term sustained experimental efforts in chasing for magnon polarons, direct spectroscopic evidence of their existence is hardly observed. Here, we report the direct observation of magnon polarons using neutron spectroscopy on a multiferroic Fe2Mo3O8 possessing strong magnon-phonon coupling. Specifically, below the magnetic ordering temperature, a gap opens at the nominal intersection of the original magnon and phonon bands, leading to two separated magnon-polaron bands. Each of the bands undergoes mixing, interconverting and reversing between its magnonic and phononic components. We attribute the formation of magnon polarons to the strong magnon-phonon coupling induced by Dzyaloshinskii-Moriya interaction. Intriguingly, we find that the band-inverted magnon polarons are topologically nontrivial. These results uncover exotic elementary excitations arising from the magnon-phonon coupling, and offer a new route to topological states by considering hybridizations between different types of fundamental excitations.https://doi.org/10.1038/s41467-023-41791-9 |
| spellingShingle | Song Bao Zhao-Long Gu Yanyan Shangguan Zhentao Huang Junbo Liao Xiaoxue Zhao Bo Zhang Zhao-Yang Dong Wei Wang Ryoichi Kajimoto Mitsutaka Nakamura Tom Fennell Shun-Li Yu Jian-Xin Li Jinsheng Wen Direct observation of topological magnon polarons in a multiferroic material Nature Communications |
| title | Direct observation of topological magnon polarons in a multiferroic material |
| title_full | Direct observation of topological magnon polarons in a multiferroic material |
| title_fullStr | Direct observation of topological magnon polarons in a multiferroic material |
| title_full_unstemmed | Direct observation of topological magnon polarons in a multiferroic material |
| title_short | Direct observation of topological magnon polarons in a multiferroic material |
| title_sort | direct observation of topological magnon polarons in a multiferroic material |
| url | https://doi.org/10.1038/s41467-023-41791-9 |
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