The primary focus of Chang’s studies is on topological materials that allow electrons to travel along their surface or edge but not in their interior. He experimentally demonstrated for the first time the quantum anomalous Hall effect in a magnetically doped topological insulator film in 2013, where impurities were intentionally introduced to impart magnetism. This work was featured in the official announcement of the 2016 Nobel Prize in Physics for David Thouless, Michael Kosterlitz and Duncan Haldane. Chang discovered the only two materials systems to date for the quantum anomalous Hall effect. The quantum anomalous Hall effect is a phenomenon where electrons in a two-dimensional plane have dissipation-free current — similar to a superconductor — that is incredibly resistant to change and is driven by internal remnant magnetism, and its realization has potential applications for reducing power consumption in future electronic and spintronic devices.
Chang's academic achievements have been honored with the Alfred P. Sloan Research Fellowship in 2018; the Army Research Office (ARO) Young Investigator Program (YIP) Award in 2018; the MIT Tech Review 35-Under-35 Innovation Award (China region) in 2018; the Young Scientist Prize from the International Union of Pure and Applied Physics (IUPAP) in 2017; and the Switzerland Dimitris N. Chorafas Foundation Award in 2013. Chang has published more than 60 scientific papers in journals including Science, Nature Materials, Nature Nanotechnology, Nature Physics, and Physical Review Letters. Chang is a member of the American Physical Society and holds five patents in both the United States and China.
Prior to joining the faculty at Penn State, Chang was a postdoctoral associate at Massachusetts Institute of Technology. He earned a doctoral degree in condensed matter physics at Tsinghua University in Beijing, China, in 2013 and a bachelor's degree in optical engineering at Shandong University in Jinan, China, in 2007.