Research

Spin Coherence in Nanomagnetic Systems

We are interested in answering a key question that underlies spintronics and quantum information science: How long can dynamic magnetic precession and flowing spins remain coherent (or "in sync") in real materials with different types and degrees of disorder?

Our experiments aim to determine phenomena that destroy coherent spin dynamics in model-system magnetic thin films (e.g., Gilbert damping, transverse spin dephasing). We also develop materials solutions to enhance spin coherence in engineered thin films. Our projects lay basic scientific foundations for possible future technologies - such as nanoscale memories that are robust against external field disturbances, computers that mimic the brain, and a semi-classical magnetic analogue of superconductivity that is operable at high temperatures.

Poor Man's Quantum Materials

We are interested in combinations of seemingly "plain" materials that show extraordinary spin-driven phenomena. A notable example is the generation of a large spin polarization by passing an electric current through thin-film conductors with sizable intrinsic and emergent spin-orbit coupling, which can be used for power-efficient switching of magnetic information.

Our experiments aim to understand how thin-film multilayers of transition metals can be engineered (e.g., by tuning crystallinity, interfaces, etc.) to yield strong spin-driven phenomena, on a par with "quantum materials" such as topological insulators, two-dimensional van der Waals materials, and complex oxides. Our approach may lead to "poor man's quantum materials" that can be synthesized and modeled more readily compared to conventional quantum materials.

Magnetic Domain Walls

The motion of magnetic domain walls – boundaries between uniformly magnetized regions – plays an important role in the switching process of the magnetization state in spintronic memory and logic devices. Domain walls also carry gradients of magnetic energy that can interact with nanoscale defects in thin-film media and with external magnetic entities (e.g., magnetic nanoparticles for biomedical applications). We examine the dynamics of domain walls in engineered magnetic thin films to understand mechanisms for faster and more stable motion.