Field-induced anisotropy in the quasi-two-dimensional weakly anisotropic antiferromagnet [CuCl(pyz)&lt;sub&gt;2&lt;/sub&gt;]BF&lt;sub&gt;4&lt;/sub&gt;

Kwon, Sungmin; Jeong, M.; Kubus, M.; Wehinger, B.; Krämer, K.W.; Rüegg, Ch.; Rønnow, H.M.; Lee, Soonchil

doi:10.1103/PhysRevB.99.214403

Field-induced anisotropy in the quasi-two-dimensional weakly anisotropic antiferromagnet [CuCl(pyz)₂]BF₄

Kwon S, Jeong M, Kubus M, Wehinger B, Krämer KW, Rüegg C, Rønnow HM & Lee S

Citation

Kwon, S., Jeong, M., Kubus, M., Wehinger, B., Krämer, K. W., Rüegg, C., … Lee, S. (2019). Field-induced anisotropy in the quasi-two-dimensional weakly anisotropic antiferromagnet [CuCl(pyz)₂]BF₄. Physical Review B, 99(21), 214403 (5 pp.). https://doi.org/10.1103/PhysRevB.99.214403

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:26059

We measured NMR and magnetic susceptibility for the quasi-two-dimensional, weakly XY-like, spin-1/2 square-lattice Heisenberg antiferromagnet [CuCl(pyz)₂]BF₄ (pyz = pyrazine = N₂C₄H₄) near the critical temperature. The Néel temperature T_N and the order-parameter critical exponent β were obtained from the NMR line broadening as a function of temperature. As the applied field strength (H ∥ c) was increased, T_N increased and β decreased. This behavior indicates that the field effectively enhanced XY anisotropy. The susceptibility as a function of temperature did not show a clear feature for T_N, but showed field-dependent minima below T_N for both H ∥ c and H ∥ ab, where minimum features disappeared for μ₀H > 2T.