Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3
© 2019 American Physical Society. Revealing the spin excitations of complex quantum magnets is key to developing a minimal model that explains the underlying magnetic correlations in the ground state. We investigate the low-energy magnons in α-RuCl3 by combining time-domain terahertz spectroscopy un...
| Main Authors: | , , , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
American Physical Society (APS)
2021
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| Online Access: | https://hdl.handle.net/1721.1/136389 |
| _version_ | 1826213207922966528 |
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| author | Ozel, Ilkem Ozge Belvin, Carina A Baldini, Edoardo Kimchi, Itamar Do, Seunghwan Choi, Kwang-Yong Gedik, Nuh |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Ozel, Ilkem Ozge Belvin, Carina A Baldini, Edoardo Kimchi, Itamar Do, Seunghwan Choi, Kwang-Yong Gedik, Nuh |
| author_sort | Ozel, Ilkem Ozge |
| collection | MIT |
| description | © 2019 American Physical Society. Revealing the spin excitations of complex quantum magnets is key to developing a minimal model that explains the underlying magnetic correlations in the ground state. We investigate the low-energy magnons in α-RuCl3 by combining time-domain terahertz spectroscopy under an external magnetic field and model Hamiltonian calculations. We observe two absorption peaks around 2.0 and 2.4 meV, which we attribute to zone-center spin waves. Using linear spin-wave theory with only nearest-neighbor terms of the exchange couplings, we calculate the antiferromagnetic resonance frequencies and reveal their dependence on an external field applied parallel to the nearest-neighbor Ru-Ru bonds. We find that the magnon behavior in an applied magnetic field can be understood only by including an off-diagonal Γ exchange term to the minimal Heisenberg-Kitaev model. Such an anisotropic exchange interaction that manifests itself as a result of strong spin-orbit coupling can naturally account for the observed mixing of the modes at higher fields strengths. |
| first_indexed | 2024-09-23T15:45:03Z |
| format | Article |
| id | mit-1721.1/136389 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T15:45:03Z |
| publishDate | 2021 |
| publisher | American Physical Society (APS) |
| record_format | dspace |
| spelling | mit-1721.1/1363892023-03-15T17:35:47Z Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3 Ozel, Ilkem Ozge Belvin, Carina A Baldini, Edoardo Kimchi, Itamar Do, Seunghwan Choi, Kwang-Yong Gedik, Nuh Massachusetts Institute of Technology. Department of Physics © 2019 American Physical Society. Revealing the spin excitations of complex quantum magnets is key to developing a minimal model that explains the underlying magnetic correlations in the ground state. We investigate the low-energy magnons in α-RuCl3 by combining time-domain terahertz spectroscopy under an external magnetic field and model Hamiltonian calculations. We observe two absorption peaks around 2.0 and 2.4 meV, which we attribute to zone-center spin waves. Using linear spin-wave theory with only nearest-neighbor terms of the exchange couplings, we calculate the antiferromagnetic resonance frequencies and reveal their dependence on an external field applied parallel to the nearest-neighbor Ru-Ru bonds. We find that the magnon behavior in an applied magnetic field can be understood only by including an off-diagonal Γ exchange term to the minimal Heisenberg-Kitaev model. Such an anisotropic exchange interaction that manifests itself as a result of strong spin-orbit coupling can naturally account for the observed mixing of the modes at higher fields strengths. 2021-10-27T20:35:09Z 2021-10-27T20:35:09Z 2019 2021-06-25T13:45:21Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/136389 en 10.1103/PHYSREVB.100.085108 Physical Review B Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Physical Society (APS) APS |
| spellingShingle | Ozel, Ilkem Ozge Belvin, Carina A Baldini, Edoardo Kimchi, Itamar Do, Seunghwan Choi, Kwang-Yong Gedik, Nuh Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3 |
| title | Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3 |
| title_full | Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3 |
| title_fullStr | Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3 |
| title_full_unstemmed | Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3 |
| title_short | Magnetic field-dependent low-energy magnon dynamics in α – RuCl 3 |
| title_sort | magnetic field dependent low energy magnon dynamics in α rucl 3 |
| url | https://hdl.handle.net/1721.1/136389 |
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