Non-equilibrium spin dynamics in correlated van der Waals antiferromagnets
Abstract: In recent decades, ultrashort optical pulses have emerged as an important tool for controlling spin dynamics in antiferromagnets. Strongly correlated materials in particular offer intriguing possibilities for unconventional pathways to manipulate spins due to their highly intertwined degrees of freedom. In this talk, I will focus on the family of correlated van der Waals antiferromagnets MPS3 (M = Ni, Mn, Fe). Using ultrafast terahertz spectroscopy, we demonstrate that the non-equilibrium driving of spin–orbit-entangled excitons in NiPS3 leads to a coherent spin precession. Moreover, we observe that this same magnon mode can be excited via markedly distinct mechanisms as we tune the pump photon energy across a broad range of the optical spectrum. These results suggest a strategy for controlling magnon dynamics based on the selective photoexcitation of electronic states. Lastly, I will discuss our efforts toward using light to modify the magnetic phases of these compounds.
About the QSQM: The EFRC-QSQM center aims to develop and apply nontrivial quantum sensing to measure and correlate local and nonlocal quantum observables in exotic superconductors, topological crystalline insulators, and strange metals. The center is led by the University of Illinois at Urbana-Champaign in partnership with the University of Illinois at Chicago and the SLAC National Accelerator Laboratory.