GRANT AWARD: New materials bring accessibility to topological insulators


Mingzhong Wu, professor, Department of Physics, College of Natural Sciences


United States Department of Energy, Office of Basic Energy Sciences

Grant amount

Three years, $375,385 total

Grant title

Room-Temperature Topological Insulator Alpha-Sn Thin Films – From Fundamental Physics to Applications

Project description

Wu’s project will explore a new topological insulator, alpha-Sn thin films. Topological insulators are materials that behave as insulators on their interiors but are conductive on their surfaces. Conventional topological insulators made from bismuth and samarium-based compounds can host both interior insulation and surface conductivity simultaneously – but only at low temperatures. This has put limitations on the research and applications of those materials.

Recent findings show that alpha-Sn thin films can host this combination of characteristics at room temperature. With this award, Wu aims to answer fundamental questions regarding the surface states in alpha-Sn thin films, namely, spin-momentum locking. Wu will further study the material’s unusual sub-surface states using approaches such as voltage gating.

This project will also examine the effects of topological surface states in alpha-Sn thin films on adjacent magnetic thin films, such as magnetic damping and anisotropy. Wu will explore the possibility of using alpha-Sn thin films to control magnetization dynamics in these films, including domain wall motion and exciting magnetization precession. Topological insulators could one day have a role in improving the efficiency of energy transfer in electronics.

More information

Public abstract