Anisotropy-governed competition of magnetic phases in the honeycomb quantum magnet Na3Ni2SbO6 studied by dilatometry and high-frequency ESR

• Verfasst von: Werner, Johannes [VerfasserIn]
• Verfasst von: Hergett, Waldemar [VerfasserIn]
• Verfasst von: Gertig, Mario [VerfasserIn]
• Verfasst von: Park, Jaena [VerfasserIn]
• Verfasst von: Koo, Changhyun [VerfasserIn]
• Verfasst von: Klingeler, Rüdiger [VerfasserIn]
• Titel: Anisotropy-governed competition of magnetic phases in the honeycomb quantum magnet Na3Ni2SbO6 studied by dilatometry and high-frequency ESR
• Verf.angabe: J. Werner, W. Hergett, M. Gertig, J. Park, C. Koo, and R. Klingeler
• Fussnoten: Die Zahlen sind im Titel tiefgestellt ; Gesehen am 28.03.2018
• Titel Quelle: Enthalten in: Physical review
• Jahr Quelle: 2017
• Band/Heft Quelle: 95(2017,21) Artikel-Nummer 214414, 7 Seiten
• ISSN Quelle: 2469-9969
• DOI: doi:10.1103/PhysRevB.95.214414
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1571496920

Abstract

Thermodynamic properties and low-energy magnon excitations of S=1 honeycomb-layered Na3Ni2SbO6 have been investigated by high-resolution dilatometry, static magnetization, and high-frequency electron spin resonance studies in magnetic fields up to 16 T. At TN = 16.5 K, there is a tricritical point separating two distinct antiferromagnetic phases, AF1 and AF2, from the paramagnetic regime. In addition, our data imply short-range antiferromagnetic correlations at least up to ∼5TN. Well below TN, the magnetic field BC1≈9.5 T is needed to stabilize AF2 against AF1. The thermal expansion and magnetostriction anomalies at TN and BC1 imply significant magnetoelastic coupling, both of which are associated with a sign change of ∂L/∂B. The transition at BC1 is associated with softening of the antiferromagnetic resonance modes observed in the electron-spin-resonance spectra. The anisotropy gap Δ=360 GHz implies considerable uniaxial anisotropy. We deduce the crucial role of axial anisotropy favoring the AF1 spin structure over the AF2 one. While the magnetostriction data disprove a simple spin-flop scenario at BC1, the nature of a second transition at BC2 ≈ 13 T remains unclear. Both the sign of the magnetostriction and Grüneisen analysis suggest that the short-range correlations at high temperatures are of AF2 type.