Materials research is at the heart of many important problems facing our nation and the world—from those concerning the more efficient use of energy to the development of a new generation of electronics. Princeton has a large group of scientists and engineers active in modern materials research across different departments on campus addressing many of these important research challenges. The PCCM’s aim is to bring together teams of faculty to address specific problems at the forefront of materials research. A defining feature of the research approach at the PCCM is the tight-knit collaborations between researchers with complementary expertise spanning materials synthesis, advanced characterization, as well as theoretical modeling. In addition to its research aim, the PCCM is also focused on bringing the excitement of materials research more broadly through its diverse education and outreach programs. Through this exposure, it aims to educate the new generation of researchers in science and engineering.
Princeton's F. Duncan Haldane receives the 2016 Nobel Prize in Physics
Professor F. Duncan Haldane, PCCM IRG-1 senior investigator, has been awarded the 2016 Nobel Prize in Physics "for theoretical discoveries of topological phase transitions and topological phases of matter." Haldane, the Eugene Higgins Professor of Physics who joined the Princeton faculty in 1990, shares the prize with David Thouless of the University of Washington and J. Michael Kosterlitz of Brown University.
(Below are excerpts from the Princeton University article by Morgan Kelly, Office of Communications.)
"They have used advanced mathematical methods to study unusual phases, or states, of matter, such as superconductors, superfluids or thin magnetic films," the Royal Swedish Academy of Sciences said in announcing the award. A currently robust area of condensed matter physics, topological phases and materials are zero-temperature phases of matter that exhibit unique properties, particularly great stability and efficient particle movement. Topological materials are considered key to finally realizing highly efficient and powerful quantum computers.
Haldane, who joined Princeton's faculty in 1990, was honored for work he began in the early 1980s, shortly after he received his Ph.D. in physics from the University of Cambridge in 1978 — the last two years of which he completed as a visiting student at Princeton. A paper published in the journal Physics Letters A in 1983 used a "toy model" to explore the meeting place of normal matter and topological matter in a single layer of a one-atom thick sheet of carbon known as graphene. The controversial paper bucked the conventional wisdom about how magnets behave, Haldane said. "At the time, it made a big stir because people said it's nonsense, it has to be wrong," he said. "It was blocked for publication, but I knew it was right." The paper eventually earned Haldane the American Physical Society's 1993 Oliver E. Buckley Condensed Matter Prize, which honors "outstanding theoretical or experimental" work.
A second paper published in 1988 in the journal Physical Review Letters used a theoretical model of two-dimensional materials to show that small materials could have topological properties, which would negate the need for huge magnetic fields. Haldane showed that in topological materials, particles move in one-way directions separated in the middle much like the lanes of a divided highway. This means quantum information could be transported at any angle without being degraded, Haldane said.
While intriguing to theorists, however, Haldane's work "sat around as an interesting toy model for a very long time — no one quite knew what to do with it," he said. Then in 2007, nearly a quarter-century after his paper in 1983, University of Pennsylvania researchers produced three-dimensional crystals exhibiting the qualities Haldane had theorized — which came as a pleasant surprise to Haldane. "I put in the first paper that this is unlikely to be anything anyone could make — I kicked myself for not noticing it before," he said, laughing. "Now, that toy model is like the hydrogen atom for topological materials — it turned out to be the first example of topological quantum matter."
In the decade since Haldane's work was materialized, topological materials have become one of the most popular fields in condensed matter physics, said B. Andrei Bernevig, a Princeton professor of physics who often works with Haldane. "Topological insulators is now one of the biggest fields in physics, one of the biggest in condensed matter physics. Because of his work, a lot of new materials have been discovered," Bernevig said. "I have hope that we'll have a materials revolution in a similar way that we had a revolution with the transistor in the '40s and '50s. There is huge promise to this area of research." He attributed Haldane's accomplishments to his enthusiasm for physics. "There is nothing he enjoys more than to work 14 to 18 hours a day just doing physics," Bernevig said. "The way he thinks about things is unlike any other person — his process is highly uncommon, which is probably why he came up with so many of the amazing things he has. He does not come up with things in consecutive order — it is in flashes of brilliance."
M. Zahid Hasan, a Princeton professor of physics whose creation of topological insulators helped confirm Haldane's models, said the Nobel win is "exciting news" for the field. "This is recognizing the early work in this field," he said. "These ideas may be abstract, but you can find a topological insulator in a rock, that is, in naturally occurring materials as well as ones we make in the lab. I can point to a piece of rock and tell you that these are topological. These Nobel laureates created a revolution in condensed matter physics, in materials science."
The 2016 Nobel physics prize emphasizes the importance of theoretical physicists, and their collaborations with experimental and materials scientists, Haldane said. "It's a vindication of ideas as opposed to measuring things or doing brute-force calculations," Haldane said. "After it became clear that these were real materials and not just theorists' dream materials, the field [of topological materials] exploded."
Robert Cava, Princeton's Russell Wellman Moore Professor of Chemistry, works with Haldane to create materials based on his theoretical models. "Duncan came to talk to me 15 or 20 years ago when he wrote his paper on the topological physics of honeycomb lattices or something like that, and was asking me if I could think of a way to put it in a material. I think it is one of those cool conversations you have in life with people," Cava said. "The theorist points us in a direction and you never know where it is going to lead," he said. "It is a beautiful kind of three-way thing with the theorists and the experimentalists and the materials makers."
Throughout the day, Haldane was asked why, after being woken up around 4:30 a.m. by a phone call from Sweden, then spending the morning speaking with press and many well wishers, would he still take 90 minutes to teach a class. "It's a matter of duty and pride to go back and do one's job," Haldane said. "This can be an inspiration for students. This, winning a Nobel Prize, has to be the dream of most of the people who start off in physics. And everyone has a chance."
Video of the Princeton University news conference on Oct. 4.
News release from the Royal Swedish Academy of Sciences (NobelPrize.org)
Video of the Nobel news conference at the Royal Swedish Academy of Sciences