Exploring Magnetic Dynamics in 2D Magnetic Heterostructures through a Microscopic and Macroscopic Lens

The discovery of spin–orbit torque (SOT) has fueled the search for materials that enable efficient, low-power magnetic control. In this talk, we will present recent results revealing SOT-driven magnetic dynamics captured by our macroscopic Cryo-Sagnac interferometer and microscopic domain structures imaged with SPLEEM. We investigate SOT-driven magnetization dynamics in van der Waals (vdW) heterostructures using a custom scanning Cryo-Sagnac magneto-optic Kerr effect (MOKE) interferometer. This technique provides sub-micron spatial resolution, nanoradian Kerr sensitivity, and vector magnetic field control, allowing non-invasive optical mapping of SOTs in both conductive and insulating devices. To access complementary microscopic information, we employ Spin-Polarized Low-Energy Electron Microscopy (SPLEEM) at the Lawrence Berkeley National Lab in the Molecular Foundry. SPLEEM directly images surface magnetization with nanometer resolution and full three-dimensional spin contrast under tunable temperature and external magnetic field. Together, these approaches offer a powerful multi-scale view of spin–orbit phenomena and interfacial magnetism in vdW systems, revealing how symmetry and current flow govern magnetic textures.