High-field electron spin resonance in the two-dimensional triangular-lattice antiferromagnetNiGa2S4

2008/07/31 by H. Yamaguchi, Hironori Yamaguchi, Shojiro Kimura +10 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Organic and Molecular Conductors Research #Physics of Superconductivity and Magnetism #cond-mat.mtrl-sci #cond-mat.str-el

paper · pdf · doi:10.1103/physrevb.78.180404

5 pages, 3 figures

arxiv created 2008/09/25 · openalex publication_date 2008/11/11 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

We report experimental results of high-field electron spin resonance (ESR) measurements in magnetic fields up to about 53 T on the quasi-two-dimensional triangular-lattice antiferromagnet NiGa₂S₄. From the temperature evolution of the ESR absorption linewidth, we find three distinct temperature regions: those (i) above 23 K, (ii) between 23 K and 8.5 K, and (iii) below 8.5 K. The linewidth is affected by the dynamics of Z₂ vortices below 23 K and one of the conventional spiral resonance modes explains well the frequency dependence of the ESR resonance fields far below 8.5 K. Furthermore, we found an anomaly in the magnetization curve around one third of the saturation magnetization for H\ensuremath⊥c, corresponding to softening of another resonance mode. These results suggest the occurrence of a Z₂ vortex-induced topological transition at 8.5 K.

Citations

• Spin Liquid State in an Organic Mott Insulator with a Triangular Lattice
• Nonmagnetic Insulating States near the Mott Transitions on Lattices with Geometrical Frustration and Implications for κ-(ET)2Cu2(CN)3

Cited by

• Signature of a Z2 Vortex in the Dynamical Correlations of the Triangular-Lattice Heisenberg Antiferromagnet