$1M Grant to Fund Work on Superconductors, Thermoelectrics, New Class of Materials

Better superconducting materials could transform the generation, transmission and storage of electricity, while new thermoelectric materials could help reduce greenhouse gases. And a new class of materials known as super-thermal-conductors could lead to more powerful microelectronics and nanoelectronics.

Researchers from the University of Houston are working to discover novel materials, funded by a $1 million grant from the Air Force Office of Scientific Research.

“This could have a major impact on modern technology and will move material research to a higher level,” said Paul Chu, T.L.L. Temple Chair of Science and founding director of the Texas Center for Superconductivity at the University of Houston (TcSUH). Chu and Bing Lv, a research assistant professor at TcSUH, are principal investigators on the grant. Lv will join the University of Texas at Dallas this fall as a tenure-track assistant professor of physics.

The work will rely upon a one-of-a-kind piece of equipment designed by Chu and UH colleagues under a 2014 grant from the Defense University Research Instrumentation Program at the Department of Defense (DOD), along with other equipment previously developed at TcSUH. The DOD grant, along with money from private endowments, provided $1.8 million to design and build the equipment, which will allow them to synthesize and study a variety of properties of different materials in situ microscopically.

The design is complete, and Chu said a build order will be submitted soon.

The three-pronged effort for new materials includes:

• Novel superconductors with higher transition temperatures, known as Tc, and higher critical current densities, known as Jc, which would allow superconducting properties at higher temperatures. The work will build upon other researchers’ recent discoveries of non-bulk superconductivity with Tc up to 100 K in iron-based superconductors: rare-earth doped CaFe2As2(Cal22) single crystals and FeSe ultrathin films. Recently reported possible superconductivity above 200 K also will be explored.
• More powerful and efficient thermoelectric materials, which produce electricity by exploiting the flow of current from a warmer area to a cooler area. They can generate electricity by capturing “waste” heat, produced by industrial, electronic and other processes, rather than relying upon fossil fuels or another energy source.
  
  Current thermoelectric materials are reliable but too inefficient for some applications. The researchers propose growing single crystals of intermetallic magnesium alloy Mg2(Sn,Ge) and related compounds, optimizing them for greater power and efficiency and studying the underlying causes and interfacial effect.
• A new class of material, super-thermal-conductors. The researchers will work with boron arsenide in an effort to create a material with thermal conductivity comparable to that of diamonds, but at a dramatically lower cost.

Scientists at UH and Boston College have used computational analysis to theoretically predict the suitability of boron arsenide for this use, and Lv has grown boron arsenide crystals. This work will focus on enhancing the thermal conductivity of boron arsenide and related compounds to reach the levels predicted by the theorists.

That could prove revolutionary for microelectronics and nanoelectronics, Chu said, because the microelectronic chips in miniature devices can generate dangerous levels of heat. A material that could quickly draw away the heat would allow more, and more powerful, electronic chips to be packed together, increasing power and function.

If work with the new materials succeeds, he said it could have a significant impact on science, as well as both military and civilian life.

“It will revolutionize the industry,” Chu said. “Whatever you do with electricity, it would get better.”

- Jeannie Kever, University Media Relations