Physics’ Ed Barnes to develop mathematical models for research into exotic topological materials
April 19, 2019
Ed Barnes of the Virginia Tech Department of Physics will use a National Science Foundation CAREER grant to create mathematical models that will help scientists understand how electrical currents flow in special compounds that possess an exotic property known as topology.
The $494,000 five-year grant will allow Barnes, an assistant professor in the Virginia Tech College of Science, to build a new mathematical framework that can be used to predict how currents induced by light or magnetic fields will flow in topological materials. The CAREER grant is considered the National Science Foundation’s most prestigious award, given to creative junior faculty likely considered to become academic leaders of the future.
One class of these compounds, known as transition metal dichalcogenides, can form amazingly thin sheets only one-atom thick. This fact, along with the compound’s topological properties, allows them to strongly absorb light and convert it into electrical currents, making them ideal for potential use in solar panels and other photo-electric technologies, such as fire alarms. But any breakthroughs are years off.
“Understanding how this process works in detail is challenging with existing mathematical techniques, which is my motivation to seek new approaches to study these compounds, which have such great potential for energy conversion,” Barnes said.
Barnes will also look at two other types of topological materials, known as topological insulators and Weyl semimetals, the latter named after German mathematician and theoretical physicist Hermann Weyl.
In these materials, electrical currents are able to flow with little resistance across the surface of the material due to topology. This feature offers the possibility of a new wave of electronics that require significantly less power to operate, reducing heating and energy consumption. Barnes seeks to understand how magnetic fields can be used to control the flow of currents in these materials and how impurities in the material might disrupt the benefits of topology.
With new topological materials that can easily absorb light and carry currents, the impact on electronics, from cell phones to computers, could be great. Especially in the realm of energy conservation.
“Making these technologies a reality requires a deep understanding of their rich physics,” Barnes said in his NSF proposal. “The goal of this project is to develop new theoretical techniques that can be used to make accurate predictions about the behavior of currents in these materials in the presence of applied electric fields, magnetic fields, or lasers. These predictions could then be used to guide further progress toward new experiments, technological applications, and advances in our fundamental understanding of topological materials and materials more generally.”
Working with Barnes will be physics graduate students Kuangyin Deng from Chongqing, China, and Arian Vezvaee from Tehran, Iran.