Regensburg 2025 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 40: Frustrated Magnets II

MA 40.9: Vortrag

Donnerstag, 20. März 2025, 17:15–17:30, H20

Easy-axis Heisenberg model on the triangular lattice: from supersolid to gapped solid — •Martin Ulaga¹, Jure Kokalj^2,3, Takami Tohyama⁴, and Peter Prelovšek³ — ¹Max Planck Institute for the Physics of Complex Systems, Dresden, Germany — ²Faculty of Civil and Geodetic Engineering, University of Ljubljana, Ljubljana, Slovenia — ³Department of Applied Physics, Tokyo University of Science, Tokyo, Japan — ⁴Jožef Stefan Institute, Ljubljana, Slovenia

We investigate the easy-axis Heisenberg model on the triangular lattice by numerically studying excitations and the dynamical spin structure factor S^µµ(q,ω). Results are analyzed within the supersolid scenario, characterized by the translation-symmetry-breaking parameter m_z and the supersolid off-diagonal order parameter m_⊥. We find very robust m_z > 0 in the whole easy-axis anisotropy regime α = J_⊥/J_z > 0, even enhanced by the magnetic field h>0. Results also support m_⊥>0 for intermediate α <1 and h>0. Still, at small α 0.2, relevant for recent experiments on the magnetic material K₂Co(SeO₃)₂, we find at h=0 rather vanishing m_⊥∼ 0, consistent with numerical evidence of a finite magnon excitation gap

Keywords: Spin supersolid; Anisotropic Heisenberg model