The research in Prof. Kent’s group focuses on spin dynamics in condensed matter, specifically magnetic materials in the form of thin film heterostructures and nanoscale devices. The fundamental questions we address are related to how spin-angular momentum is created, transported and detected in ferromagnets, ferrimagnets and antiferromagnets and many different types of nanostructures. We explore this experimentally using high-frequency and high-speed probes of magnetic response, magnetic and electronic transport measurements, resonant x-ray microscopy imaging techniques, thin film deposition and sample nanofabrication. Importantly, we probe the material response on the fundamental frequency/time and spatial scales at which it occurs (not averaged over the time and spatial scales of the response). We also develop theoretical models of magnetic behavior as well as computational techniques, such as micromagnetics.
For ferromagnetic materials the fundamental frequencies are GHz and great (>10^9 Hz) and the time scales are sub-nanosecond. In high-frequency experiments, we use ferromagnetic resonance spectroscopy and a local version of this technique called spin-torque driven ferromagnetic resonance. The spatial scales of magnetic domains are typically 10s of nanometers, which we image with scanning transmission x-ray microscopy (STXM) and photoemission electron microscopy (PEEM). We measure magnetic susceptibility using vibrating sample magnetometry and typically create magnetic heterostructures using physical vapor deposition.
The following are a selection of projects we are presently working on. For more information on our research please contact Prof. Kent and members of his group.