Excitations in the ordered and paramagnetic states of honeycomb magnet Na2Co2TeO6
Autor: | Yao, Weiliang, Iida, Kazuki, Kamazawa, Kazuya, Li, Yuan |
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Rok vydání: | 2022 |
Předmět: | |
Zdroj: | Physical Review Letters 129, 147202 (2022) |
Druh dokumentu: | Working Paper |
DOI: | 10.1103/PhysRevLett.129.147202 |
Popis: | Na2Co2TeO6 is a proposed approximate Kitaev magnet, yet its actual magnetic interactions are elusive due to a lack of knowledge on the full excitation spectrum. Here, using inelastic neutron scattering and single crystals, we determine the system's temperature-dependent magnetic excitations over the entire Brillouin zone. Without committing to specific models, we unveil a distinct signature of the third-nearest-neighbor coupling in the spin waves, which signifies the associated distance as an emerging "soft link" in the ordered state. The presence of at least six non-overlapping spin-wave branches is at odds with all models proposed to date. Above the ordering temperature, persisting dynamic correlations can be described by equal-time magnetic structure factors of a hexagonal cluster, which reveal the leading instabilities. Our result sets definitive constraint on theoretical models for Na2Co2TeO6 and provides new insight for the materialization of the Kitaev model. Comment: 4 pages, 4 figures plus Supplemental Material; comments are welcome |
Databáze: | arXiv |
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