Low-dimensional antiferromagnetic fluctuations in the heavy-fermion paramagnetic ladder UTe$_2$
| Autor: | Knafo, W., Knebel, G., Steffens, P., Kaneko, K., Rosuel, A., Brison, J. -P., Flouquet, J., Aoki, D., Lapertot, G., Raymond, S. |
|---|---|
| Rok vydání: | 2021 |
| Předmět: | |
| Zdroj: | Phys. Rev. B 104, 100409 (2021) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevB.104.L100409 |
| Popis: | Inelastic-neutron-scattering measurements were performed on a single crystal of the heavy-fermion paramagnet UTe$_2$ above its superconducting temperature. We confirm the presence of antiferromagnetic fluctuations with the incommensurate wavevector $\mathbf{k}_1=(0,0.57,0)$. A quasielastic signal is found, whose momentum-transfer dependence is compatible with fluctuations of magnetic moments $\mu\parallel\mathbf{a}$, with a sine-wave modulation of wavevector $\mathbf{k}_1$ and in-phase moments on the nearest U atoms. Low dimensionality of the magnetic fluctuations, consequence of the ladder structure, is indicated by weak correlations along the direction $\mathbf{c}$. These fluctuations saturate below the temperature $T_1^*\simeq15$~K, in possible relation with anomalies observed in thermodynamic, electrical-transport and nuclear-magnetic-resonance measurements. The absence or weakness of ferromagnetic fluctuations, in our data collected at temperatures down to 2.1 K and energy transfers from 0.6 to 7.5 meV, is emphasized. These results constitute constraints for models of magnetically-mediated superconductivity in UTe$_2$. Comment: 6 pages, 4 figures, + Supplementary Materials (6 pages, 6 figures) |
| Databáze: | arXiv |
| Externí odkaz: |
|