Interactions between spin wave and magnetic domain structures

Non-Technical Description

Spin wave is a useful way to transfer energy and information inside solid state materials. It is considered as one of the promising building blocks for next generation microelectronic technologies. Compared with existing computing devices, the ones based on spin wave can have lower power consumption, higher speed and are compatible with parallel operations.

In order to realize computing devices based on spin wave, some bottlenecks need to be overcome. Particularly, one has to control the flow of spin wave inside solid materials. This project utilizes a novel mechanism to control the spin wave flow, which is intrinsically compact and consumes little energy.

The fundamental knowledge achieved in this project has direct microelectronic applications and can lead to new device structures for information storage and computing. The research and education efforts ensure students at different levels benefit from the research and get trained to master cross-disciplinary techniques used in this project. The project not only educates and trains the next generation scientists and engineers but also assists to place them in microelectronic industry after graduation.

Technical Description

The study on the interactions between spin current and the dynamics of nanoscale magnetic structures has been a very active research area within spintronics. The non-uniform magnetic textures-induced magnetoresistance and the spin current-caused magnetic switching have both led to important industrial applications. However, existing research mostly employ conduction electrons to carry spin current.

The other useful way of transferring spin angular momentum within solid state materials, i.e., to use spin wave, has remained largely unstudied experimentally, despite the theoretical prediction on the rich physics that can be caused by the interactions between spin wave and magnetic structures. This project focuses on quantitatively studying the influence of magnetic textures on the transport of magnon spin current, as well as the magnonic spin torque induced magnetic switching.

Particularly, the project aims to achieve quantitative understanding between spin wave transport and the internal structures of domain wall as well as topological magnetic textures. The project enhances people’s understanding on the spin current transport enabled by magnons and results in new ways of controlling magnetic ordering in solids. This project has applications in microelectronic industry on making better interconnections and leads to new device schemes for information storage and computing.

Integrated research and education efforts are established through the project so that students at K12, undergraduate and graduate levels benefit from the research, who are trained to master cross-disciplinary techniques used in this project, including material synthesis and characterization, nanoscale device fabrication and microwave circuit design and measurement.

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.