GOALI: Spin-Orbit Torques From Magnetically Ordered Materials and Their Applications

Non-Technical Abstract:

This project brings together leading researchers from New York University and IBM with the aim of furthering the understanding and application of nanometer scale magnetic devices and materials. Magnetic nanostructures are widely used in technology with the most advanced applications found in the semiconductor industry. This is associated with the fact that there can be large reductions in energy usage when information is stored and processed with magnetic materials; because data stored in magnetic materials can be retained without power (or a battery in mobile devices).

Because of ever-increasing worldwide demands for data processing and storage, advanced magnetic devices form the backbone of huge industries in the United States. This project aims to uncover more efficient means of writing magnetic information using magnetic materials themselves as the source of spin-orbit torques. The project is integrated with the training of young scientists in this forefront area of magnetism research.

Graduate and undergraduate students involved in this collaboration will gain by interactions between academia and industry and will be enriched through exposure to a variety of perspectives, expertise and techniques present in an industrial setting. Technical Abstract:

This NSF-GOALI project brings together leading researchers in nanomagnetism from New York University and IBM with the aim of furthering the understanding and application of spintronics. An important and overarching goal of spintronics is to discover and characterize more efficient means of generating spin currents and associated spin torques on magnetization.

Recently it has been established that spin-orbit interactions enable very efficient charge-to-spin conversion and large torques on magnetic layers. However, the spin polarization that acts on the ferromagnetic layer is typically confined to the layer plane, and thus is very effective at reversing the magnetization of in-plane magnetized layers but far less effective in switching and exciting the magnetization of perpendicularly magnetized elements.

This project investigates spin currents associated with spin-orbit coupling in ferromagnetic layers and their interfaces to nonmagnets, which have the potential to generate spin currents polarized perpendicular to the layer planes. The charge-to-spin conversion efficiency and the symmetry of the response are studied for a variety of transition metal materials and interfaces as a function of magnetization angle.

Time-resolved and spatially resolved probes of magnetization dynamics are employed to reveal magnetization switching mechanisms in thin perpendicularly magnetized layers and patterned nanostructures to further the understanding of the nonlinear magnetization dynamics excited by spin-transfer torques. Graduate and undergraduate students involved in this collaboration will gain by interactions between academia and industry and through student exchanges between NYU and IBM.

Their education will be enriched through the variety of perspectives, expertise and techniques present in an industrial setting. High school students will also be encouraged to participate in this research project. As part of this project the PIs will develop a new course at NYU on Physics and Technology with the goal of introducing students to physics in the “real world” (outside of universities).

The course will highlight the skills needed to apply physics to commercialize technologies and impact society more broadly in technological fields, including in magnetism and quantum information.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.