A pioneer in nanotechnology
The 2016 Wolf Prize in Physics will go to Prof. Yoseph (Joe) Imry, professor emeritus of the Department of Condensed Matter Physics at the Weizmann Institute of Science, a pioneer in the physics of mesoscopic systems—systems are much smaller than everyday objects but larger than atoms, and random systems. The Prize will be awarded at a ceremony hosted by the President of Israel, Reuven Rivlin, in the Knesset on June 2.
The awardees were announced at an event on Jan. 13 which was attended by the Minister of Education and Wolf Foundation Chairman, Knesset Member Naftali Bennett; and Nobel laureate Prof. Dan Shechtman, Vice Chairman of the Wolf Foundation and a previous Wolf Prize winner himself. The five awards of $100,000 each will be divided between seven winners from three countries: Israel, the U.S., and Canada. Prof. Imry is the only Israeli awardee.
From Soreq to the lab
As a youngster who was enthralled with airplanes, Prof. Imry planned to be an aeronautics engineer. “I never thought I’d be a scientist,” he says. But as a master’s student in physics at Hebrew University, his instructor took notice of him when he wrote a highly creative answer on a physics test and he told the young student that he had a future in physics and at the Hebrew University. After serving as an instructing officer in the IDF’s armored corps, he began working at the Soreq Nuclear Research Center under the auspices of the Israel Atomic Energy Commission. At Soreq, he worked under Prof. Israel Pelah, who was also a professor of physics at the Weizmann Institute.
“I loved working with Israel and so I decided to do my PhD under his guidance,” recalls Prof. Imry. His research focused on proton dynamics in hydrogen-based systems. At the end of his studies, in 1966, he sat in on a lecture by a well-respected physicist. It was the moment that solidified his drive to become a research physicist—and not because it was so inspirational, he says. “I thought his whole concept was incomplete, and I was convinced that I had a new way of thinking about it, emphasizing small systems. The research community believed that such small—nano-level—systems were not important in physics,” he says. “So I spent the next three years working on a paper that contradicted that.” That paper was eventually published, but, he says, “It wasn’t much appreciated by the community.”
He went on to do his postdoctoral training at Cornell University and returned to Israel as a faculty member at Tel Aviv University, where he spent the next 17 years and realized quite early on that these nano systems are very relevant in the eventual miniaturization of electronic devices. He joined the Weizmann Institute in 1986. At the Institute, he was the driving force behind the creation of the Joseph H. and Belle R. Braun Center for Submicron Research and the Department of Condensed Matter Physics, and helped establish the Weizmann Institute as a world leader in nano-scale physics, the basis for today’s nanotechnology.
A small world with outsized impact
Classical mechanics, electricity and thermodynamics were the paradigm theories describing the world around us until the beginning of the 20th century. During the three first decades of the 20th century, quantum theory was developed in order to describe phenomena that were inconsistent with classical mechanics. While the classical theories describe the macroscopic world of large objects, quantum mechanical theory describes the microscopic world of nuclei, atoms, and small molecules.
Some of the natural questions advanced by researchers were: Where do the boundaries between the microscopic and the macroscopic worlds lie? How does the transition occur? What controls the behavior of systems in this mesoscopic scale in between the micro and macro? Are there new phenomena emerging in this regime? What is the importance of randomness created by a number of particles that is big enough to have disordered behavior but too small to average over the fluctuations?
Mesoscopic physics is the field that emerged from these questions. Prof. Imry was a key player in the development of the principal concepts of this discipline, which is a foundation of nanoscience and nanotechnology. On the macroscopic scale, quantum effects are seen only in superconductors and superfluids. He predicted that at mesoscopic scales, quantum effects would be observed also in ordinary metals. For instance, Prof. Imry, following an older paper by himself and Leon Gunther, showed, together with Rolf Landauer and Markus Buttiker, that a spontaneous persistent electric current—a current without the need for an energy source like a battery—may exist in small rings made of normal conductors.
Prof. Imry has also provided pioneering insights into the physics of phase transitions between different phases of matter. His work on phase transitions in finite systems and low dimensions is crucial for both statistical mechanics and mesoscopic physics. His theory of phase transitions in random fields with Shang-keng Ma is a seminal contribution that has influenced the whole statistical physics community. Similarly, his analysis of the metal-insulator transition, including the derivation of experimentally testable scaling laws, has had a profound influence on the condensed matter community. His discussion with Prof. Moshe Schwartz of Tel Aviv University of Bose-Einstein condensation in solid He4 came three decades before the explosion of research on super-solids.
The Wolf Prize panel said that Prof. Imry “is a physicist with impressive foresight, often well ahead of his time, who has spearheaded several fields of physics. For all these reasons he has been awarded the 2016 Wolf prize in Physics.”
Today, says Prof. Imry, who is 77 and lives in Tel Aviv, he continues to conduct research, including a different field: energy efficiency and conversion. He also serves as an advisor to Landa Labs, which develops nano-materials for these and other applications.