Precision spectroscopy of van der Waals magnets in and out of equilibrium

The emergence of van der Waals magnets has opened remarkable opportunities to uncover magnetic states of matter with no analogue in the bulk limit. Through precision optical spectroscopy spanning both equilibrium and ultrafast regimes, we demonstrate how dimensionality, magneto-crystalline anisotropy, and relativistic interactions intertwine to generate unconventional magnetic orders and exotic collective excitations in this class of materials. Furthermore, by integrating linear and nonlinear optical probes, we resolve characteristic coupling strengths in resonance with low-energy modes, providing a direct window into the dynamics of symmetry breaking, chirality, and magnetoelectric correlations in the two-dimensional limit. Beyond their fundamental implications, these experiments establish new avenues for manipulating correlated spin systems in atomically thin magnets, advancing prospects for spintronic architectures, quantum sensing, and light-driven quantum technologies.