The David Pines Symposium on Superconductivity Today and Tomorrow

Siv Schwink

David Pines at a blackboard. Image scanned at the AIP Emilio Sègre Visual Archives.
David Pines at a blackboard. Image scanned at the AIP Emilio Sègre Visual Archives.
A symposium honoring the late Center for Advanced Study Professor Emeritus of Physics and of Electrical and Computer Engineering David Pines is taking place on March 29 and 30 at the Institute for Condensed Matter Theory (ICMT) of the University of Illinois at Urbana-Champaign. At the David Pines Symposium on Superconductivity Today and Tomorrow, 20 invited speakers will cover today’s most pressing problems and most promising directions in superconductivity. Some of the talks will also address other research topics that were of special interest to Pines, including Fermi liquids and topics in nuclear physics and astrophysics.

The symposium is being sponsored jointly by the Gordon and Betty Moore Foundation, by the Illinois Department of Physics, by the Illinois College of Engineering, and by the Illinois Center for Advanced Study. Travel funds for students attending the symposium were provided by the National Science Foundation.

The symposium is being organized by Professor Andrey Chubukov (University of Minnesota), Professor Jörg Schmalian (Karlsruhe Institute of Technology), and by current Director of the ICMT and Professor Eduardo Fradkin. Both Chubukov and Schmalian were postdocs in Urbana in the 1990s working closely with David Pines.

Pines, one of the foremost condensed matter theorists of his generation, died on May 3, 2018, in Urbana, Illinois, at the age of 93. He was a student of Joseph Weinberg, Robert Oppenheimer, David Bohm, and John Bardeen. Pines is remembered for his many ground-breaking accomplishments in condensed matter physics.

With Bohm, Pines established the collective nature of electron-electron interactions in solids by formulating the random phase approximation (RPA), the basis of the current understanding of screening in metals.

With Bardeen, Pines showed that in a dense fermionic system the electron-phonon attractive interaction can overcome the Coulomb repulsion between electrons. This discovery led directly to the discovery of the mechanism that underlies the Bardeen Cooper Schrieffer theory of superconductivity. Pines had a life-long interest in superconductivity, making seminal contributions to our understanding of heavy fermions and of the high temperature superconductors.

Pines is also noted for porting new approaches across disciplines to elucidate complex systems and emergent behavior, helping to chart the earliest course of inquiry in many-body physics. In nuclear physics, he helped to elucidate the collective motion in nuclei, and in particular of pairing in nuclei (with Aage Bohr and Ben Mottelson), and in theoretical astrophysics, he provided early input on the structure and development of neutron stars.

Pines spent the bulk of his academic career at Illinois Physics. His first stint from 1952 to 1955 was as Bardeen’s first postdoc, with the academic title research assistant professor. He returned in 1959, joining the U of I faculty as a professor of physics and electrical engineering.

Fradkin notes, “This symposium is a fitting way to celebrate David Pines and his legacy, while celebrating the excitement over what’s yet to come in our field. Our speakers are leading experimentalists and theorists, many of whom had a special connection to David Pines. Among our younger speakers are scientists whose work continues what Pines and his cohort started. When we say that our faculty today stands on the shoulders of giants, we are talking about the likes of David Pines and his cohort—Tony Leggett, Chris Pethick, Gordon Baym, and many others. These giants in the history of condensed matter theory and experiment really laid the groundwork for the promising work being done in superconductivity today, not just here, but around the world.”

In addition to his scientific research contributions, Pines was also well known for the instrumental role he played in bringing prominent scientists together to explore the big scientific questions of his time. He was the founding director of the Center for Advanced Study from 1967 to 1970 at Illinois. He served as vice president of the Aspen Center for Physics from 1968 to 1972. He was one of the key organizers and founding members of the Santa Fe Institute (SFI) in 1984; he later played a variety of organizational roles for the institute, most recently holding the title of co-founder in residence. And in 1999, he co-founded the Institute for Complex Adaptive Matter, a virtual campus collective of scientists, and served as its first director and on its board of trustees and science steering committee; in 2004, he cofounded its international component I2CAM.

Pines was a dedicated teacher and his work as an author and editor likewise facilitated scientific advances in several branches of physics. In addition to producing hundreds of peer-reviewed scientific articles, Pines was the founding editor (1961–1981) of Frontiers in Physics, a lecture-note and reprint series. He served as editor of the American Physical Society’s Reviews of Modern Physics (1973–1996), reinvigorating the publication and making it one of today’s leading physics journals. And he served many years on the editorial boards of the Journal of Physics and Chemistry of Solids and of the SFI’s Studies in the Sciences of Complexity.

Generations of condensed matter theorists were educated by Pines’ physics textbooks, which have been widely used in the US and abroad. Because of his focus on communicating complex science through basic concepts, these volumes are still relevant to the teaching of physics today: The Many-Body Problem (1961; in Russian, 1963); Elementary Excitations in Solids, (1963; in Russian 1965; in Japanese, 1974); and the two-volume treatise (with Philippe Nozières) Theory of Quantum Liquids (1967; in Russian, 1968). With economics Nobel laureate Kenneth Arrow and Philip W. Anderson, Pines edited the volume The Economy as a Complex Evolving System, summarizing a series of SFI workshops on complexity economics.

Pines was the recipient of numerous honors over the course of his long and productive career. He was elected a member of the National Academy of Sciences and of the American Philosophical Society; he was elected a Fellow of the American Academy of Arts and Sciences, of the American Association for the Advancement of Science, of the American Astronomical Society, and of the American Physical Society. He was an honorary member of the Hungarian Academy of Sciences and a foreign member of the Russian Academy of Sciences and of the Science Academy Society of Turkey. He was selected a Fellow of the J.S. Guggenheim Memorial Foundation (1962 and 1969); won the 1983 Friemann Prize in Condensed Matter Physics; was awarded the 1984 Dirac Silver Medal for the Advancement of Theoretical Physics and the 1993 Tau Beta Pi Daniel C. Drucker Eminent Faculty Award of the U of I College of Engineering; was conferred an honorary degree from the University of St. Andrews in Scotland (2009); received the 2009 John Bardeen Prize of the International Conference on the Materials and Mechanisms of Superconductivity; and received the 2013 John David Jackson Excellence in Graduate Physics Education Award of the American Association of Physics Teachers.

Recent News

  • Research

An international team of researchers led by Paul Scherrer Institute postdoctoral researcher Niels Schröter now provide an important benchmark for how "strong" topological phenonena can be in a real material. Writing in Science, the team reports experiments in which they observed that, in the topological semimetal palladium gallium (PdGa), one of the most common classifiers of topological phenomena, the Chern number, can reach the maximum value that is allowed in any metallic crystal. That this is possible in a real material has never been shown before. Moreover, the team has established ways to control the sign of the Chern number, which might bring new opportunities for exploring, and exploiting, topological phenomena. Illinois Physics Professor Barry Bradlyn contributed to the theoretical work elucidating the team's experiments.

At the European Organization for Nuclear Research (CERN), over 200 physicists across dozens of institutions are collaborating on a project called COMPASS. This experiment (short for Common Muon and Proton Apparatus for Structure and Spectroscopy) uses CERN’s Super Proton Synchrotron to tear apart protons with a particle beam, allowing researchers to see the subatomic quarks and gluons that make up these building blocks of the universe. But particle beams aren’t the only futuretech in play – the experiments are also enabled by a heavy dose of supercomputing power.

New findings from physicists at the University of Illinois, in collaboration with researchers at The University of Tokyo and others, clarify the physics of coupling topological materials with simple, conventional superconductors.

Through a novel method they devised to fabricate bulk insulating topological insulator (TI) films on superconductor (SC) substrates, the researchers were able to more precisely test the proximity effect, or coupling when two materials contact one another, between TIs and SCs. They found that when the TI film is bulk insulating, no superconductivity is observed at the top surface, but if it is a metal, as in prior work, strong, long-range superconducting order is seen. The experimental efforts were led by physics Professor Tai-Chang Chiang and Joseph Andrew Hlevyack, postdoctoral researcher in Professor Chiang’s group, in collaboration with Professor James N. Eckstein’s group including Yang Bai, Professor Kozo Okazaki’s Lab at The U. of Tokyo, and five other institutes internationally. The findings are published in Physical Review Letters, which has been highlighted as a PRL Editors’ Suggestion.

  • Accolades

Illinois Physics Assistant Professor Barry Bradlyn has been selected for a 2020 National Science Foundation CAREER (Faculty Early Career Development) Award. This award is conferred annually in support of junior faculty who excel in the role of teacher-scholars by integrating outstanding research programs with excellent educational programs. Receipt of this award also reflects great promise for a lifetime of leadership within the recipients’ respective fields.

Bradlyn is a theoretical condensed matter physicist whose work studying the novel quantum properties inherent in topological insulators and topological semimetals has already shed new light on these extraordinary systems. Among his contributions, he developed a real-space formulation of topological band theory, allowing for the prediction of many new topological insulators and semimetals.