Fig. 2: Recovery dynamics of AF orders after optical stimulation.
From: Liquid-like spin dynamics in a hybrid Heisenberg-Ising antiferromagnet
Delay curves (circles) for Sr3Ir2O7 (a), Sr2IrO4 (b), and Sr5Ir3O11 (c), with corresponding fitted curves (solid lines) spanning from −1 to 1000 ps, separated into fast (-1 to 3 ps) and slow (3 to 1000 ps) timescales. The latter is plotted on a logarithmic scale. The data for pump fluence of 2.30, 2.35 and 1.85 mJ/cm2 are shown for Sr3Ir2O7, Sr2IrO4 and Sr5Ir3O11, respectively. Error bars indicate the standard deviations from multiple measurements. The magnetic reflection of Sr5Ir3O11 is measured at (−1 0 8) to minimize the DL contribution27. The intensities of delay curves are normalized to −1 at their minima. d Pump fluence dependence of the fast recovery time constants. Error bars are the standard errors of the estimated parameters obtained from the fitting. e–h Transient equilibrium Landau free energies (solid curves) after an optical pump pulse at t = 0 (left panel) and time profiles simulated for order parameters (right panel) for ψ0 = 1.0 (e), 0.7 (f), 0.6 (g), and 0.1 (h). The schematic in e visualizes the recovery process. The potential well shown by the dashed line represents the Landau free energy immediately after the arrival of an optical pump pulse, leading to the decay of the order parameter. Over several picoseconds, the Landau free energy evolves to a transient equilibrium state (solid curves) with partial recovery of the AF order (solid green arrow).
