| Title: |
Helical spin dynamics in commensurate magnets A study on brochantite, Cu4SO4 OH 6 |
| Authors: |
Nikitin, S.E.; Xie, T.; Gazizulina, A.; Ouladdiaf, B.; Velamaz n, J.A.R.; D az Ortega, I.F.; Nojiri, H.; Anovitz, L.M.; Dos Santos, A.M.; Prokhnenko, O.; Podlesnyak, A. |
| Source: |
Physical Review Research 5 2023 , p. 033111 1 9 |
| Publication Year: |
2023 |
| Collection: |
Helmholtz Zentrum Berlin (HZB): Publications |
| Subject Terms: |
antiferromagnetism; spin waves |
| Description: |
We report the direct observation of a commensurate ordered antiferromagnetic AFM state but incommensurate helical spin dynamics in the natural mineral brochantite Cu4SO4 OH 6 through neutron diffraction and neutron spectroscopy measurements. Inelastic neutron scattering measurements reveal magnonlike excitations with considerable dispersion along the c axis and almost flat branches in other principal directions, indicating the strong one dimensional character of the magnetic correlations. We experimentally observe the effect of the uniform Dzyaloshinskii Moriya DM interaction, which elevates the degeneracy of the spin wave modes, shifting them in opposite directions in reciprocal space. The system has a commensurate AFM ground state, stabilized by the anisotropic symmetric Heisenberg exchange interactions, and quasi one dimensional chiral spin dynamics due to the antisymmetric DM interaction. Employing linear spin wave theory, we were able to construct an effective Heisenberg Hamiltonian. We quantify both the symmetric exchange parameters and the DM vector components in Cu4SO4 OH 6 and determine the mechanism of the magnetic frustration. Our work provides detailed insights into the complex dynamics of the spin chain in the presence of uniform DM interaction |
| Document Type: |
article in journal/newspaper |
| File Description: |
application/pdf |
| Language: |
unknown |
| Relation: |
info:eu-repo/grantAgreement/EU/H2020/884104 |
| Availability: |
https://www.helmholtz-berlin.de/pubbin/oai_publication?VT=1&ID=109903 |
| Rights: |
info:eu-repo/semantics/openAccess |
| Accession Number: |
edsbas.30C49415 |
| Database: |
BASE |