Fig. 1: Temperature dependence of the low-energy spin excitations in TbMn6Sn6.
From: Orbital character of the spin-reorientation transition in TbMn6Sn6
The evolution of the low-energy ferrimagnetic spin waves, plotted as χ″(q, E)/E. Inelastic neutron scattering (INS) data are shown along the a (H, 0, 1) and b (H, 0, 2) directions at T = 100, 150, 200, 240, 300, and 350 K through the spin-reorientation (SR) transition at TSR = 310 K. Insets at higher energy in a and b correspond to data along (H, 0, 3). At 100 K, the dashed and solid lines correspond to the ground state dispersion as obtained from fits to the Heisenberg model described in Ref. 24. Calculations of the spin dynamics in the random-phase approximation (RPA) are shown along the c (H, 0, 1) and d (H, 0, 2) directions at the same temperatures as the data. In a and b in the SR-phase at 350 K, the dashed and solid lines correspond to the RPA dispersions obtained using the Heisenberg parameters and a magnetically isotropic Tb ion. Thinner lines at other temperatures are guides to the eye.
