Penn Physics professors Eugene Mele and Charles Kane won the $3 million 2019 Breakthrough Prize in Fundamental Physics for their work on topological insulators.
Founded in 2011 by high-profile figures such as Priscilla Chan and Mark Zuckerberg, the Breakthrough Prize recognizes individuals internationally who produce groundbreaking research in the life sciences, fundamental physics, and mathematics. Laureates are nominated by past winners while the founding board vets the nominations.
Mele and Kane earned the reward for their theoretical discovery of a new class of materials called topological insulators, an innovation that has important implications such as improving performance of electronics and memory devices.
However, Mele said that these applications are less interesting.
“It’s standard architecture with new building blocks,” Mele said. “The thing that’s more interesting is when you hand people a new platform and they invent new architecture.”
Such architecture may lie in quantum computing, which Kane calls one of "the big technological challenges of the coming century."
A quantum computer would be able to perform faster calculations than an ordinary computer. Kane said that topological insulators have a special property when combined with a super conductor, leading to a new way to store quantum information.
Before their innovative work, “scientists thought that all insulators were the same,” Mele said. “The world view in classical electromagnetics is that conductors are cool and insulators are boring, and I think the modern view flips it on its tail."
Most insulators cannot conduct at all because they have no electric current, or flow of electrons. What makes topological insulators unique is their ability to conduct solely on their surface.
Kane likened a topological insulator to a Hershey’s Kiss.
“The wrapper is the electrical conductor, but the inside is the insulator,” Kane said.
The conductive surface state remains conserved even if the insulator is "pulled apart," Mele said.
“If you were to cut it open, then it would still be wrapped," Kane said, again using the Kiss analogy. "There's no way of taking [the wrapper] off. In a sense, it has to be there. It's topologically protected."
Topological insulators help organize currents of electrons. Instead of a crowded hallway full of people trying to get to class, Kane compared the flow of electrons on the boundary of topological insulators to split, two-way airport walkways.
Having worked together on their first paper in the late 90s, Mele said that he enjoyed collaborating with Kane, with whom he shares an office space across from in David Rittenhouse Laboratories.
“We have complementary but not congruent skills, so that helped us out,” Mele said.
Kane also said that Mele hired him and was the first person he met at Penn.
“He’s been my colleague, and he’s been my mentor,” Kane said.
Mele said that he is unsure of how he is going to use the money, but most likely some of it is going to home refurbishment.
Mele and Kane acknowledged the work that other faculty and graduate students also contributed to the research.
“I’m really delighted that Penn gets recognized for this activity, but there were a dozen people who blew the lid off the problem over the first couple of years,” Mele said. “I think we’re celebrating all their contributions. I’d like to think that we’re celebrating the field.”
College senior Ali Ghorashi works with Mele on his research and said that he anticipated Mele would win another award based on the prizes he had won in the past.
“[Mele] is an extremely humble individual,” said Ghorashi. “He’s always had plenty of time for me even though he is a busy person.”
They will receive the award at a Nov. 4 ceremony at the NASA Ames Research Center in California.