Shoucheng Zhang wins Franklin Medal in Physics

Shoucheng Zhang
Shoucheng Zhang has won the 2015 Benjamin Franklin Medal in Physics (Photo: Linda Cicero)

SHOUCHENG ZHANG, professor of physics, has been named a recipient of the 2015 Benjamin Franklin Medal in Physics, one of the oldest and most prestigious science awards in the United States.

Zhang shares the 2015 physics recognition with Charles Kane and Eugene Mele, both of the University of Pennsylvania, for their “groundbreaking theoretical contributions leading to the discovery of a new class of materials called topological insulators, and for their prediction of specific compounds exhibiting the novel properties expected of these new materials.”

“I’m deeply honored. Benjamin Franklin was my hero since childhood,” said Zhang, J. G. Jackson and C. J. Wood Professor of Physics and professor, by courtesy, of applied physics. “You’ve heard the stories, like with flying the kite in the thunderstorm. He made heroic efforts with science. He was someone who would risk his life for scientific study.

“I just use a pencil and paper,” Zhang acknowledged with a laugh.

Topological insulators are one of the most exciting topics in condensed-matter physics, with a wide range of potential practical applications. The materials function as insulators on the inside, but they conduct electricity on their surface; this conductivity is “topologically protected,” so the state of the electrons passing on the surface cannot be changed or destroyed.

Because the conducting electrons arrange themselves along the surface – “spin-up” electrons travel in only in one direction, “spin-down” electrons go only the opposite – the material could be useful for building a practical “spintronic” device that reads an electron’s spin, rather than its charge. There is a worldwide race to apply topological insulators to integrated circuits in order to extend the life of Moore’s law.

Unlike most exotic phases of matter, topological insulators were predicted theoretically before they were discovered experimentally. Zhang predicted the first topological insulator material in mercury telluride, which was confirmed experimentally soon after by a group at the University of Wurzburg in Germany.

The Franklin Institute was founded in 1824 in honor of America’s first scientist, Benjamin Franklin, and the medal is meant to reflect his spirit of discovery by recognizing significant accomplishments in science and technology. Past recipients include Thomas Edison, Marie Curie, Nikola Tesla, Albert Einstin, Jane Goodall and Bill Gates. Franklin Institute laureates have won a total of 118 Nobel Prizes.

The medal will be awarded April 23, 2015, at a ceremony in Philadelphia.