On September 12, 2026, John Michael Kosterlitz, the 2016 Nobel laureate in Physics and Emeritus Professor of Physics at Brown University, was invited to visit Nanjing University. As the guest of honor at the 28th session of the Xianlin Forum, he delivered an academic lecture titled "Phase Transitions and Dimensional Crossover in Layered Confined Solids" in the Lecture Hall at Gulou campus.
Gao Fang, Assistant President of NJU attended the lecture and delivered a speech, warmly welcoming and sincerely thanking Professor Kosterlitz for his visit on behalf of the university. She reflected on the profound heritage of NJU's physics discipline and the development of the National Laboratory of Solid State Microstructures. She highly praised Kosterlitz's foundational contributions to the research on two-dimensional topological phase transitions and expressed heartfelt congratulations on his election as a Fellow of the Royal Society in May this year. Gao remarked on the existing cooperative foundation between Professor Kosterlitz and NJU and expressed hope that this occasion would mark a new starting point in further deepening collaboration in scientific research and talent cultivation, ultimately benefiting more young faculty and students.
As part of the event, both a ceremony for Professor Kosterlitz's appointment as an NJU Distinguished Guest Professor and a plaque unveiling for the Xianlin Forum were held. Assistant President Gao presented Professor Kosterlitz with the certificate of appointment and pinned the NJU emblem on him. Professor Sun Jian, Deputy Dean of NJU's Office of Science and Technology, presented him with a commemorative plaque for the Xianlin Forum.
During the academic lecture, Professor Kosterlitz introduced the structure and melting behavior of layered confined solids. He provided an in-depth explanation of the phase transition mechanisms during the evolution of materials from two-dimensional to three-dimensional states and shared the physical insights behind the research. This research was a collaboration between him and Professor Sun Jian’s team at Nanjing University, with the results published in the Proceedings of the National Academy of Sciences (PNAS) in 2025. The lecture was accessible yet profound, and the audience frequently broke into applause.
After the lecture, enthusiastic faculty and students engaged with Professor Kosterlitz, asking questions about two-dimensional melting mechanisms, interlayer coupling effects, prospects for experimental verification, and other topics. Even after the Q&A session ended, many attendees gathered around the speaker's podium, seeking further advice, which the professor patiently provided. He also posed for photos with the students.
John Michael Kosterlitz, recipient of the 2016 Nobel Prize in Physics, is a Member of the U.S. National Academy of Sciences, a Member of the American Academy of Arts and Sciences, and a Fellow of the Royal Society. He is an Emeritus Professor of Physics at Brown University and currently a Chair Professor and Honorary Dean of the Institute of Quantum Science and Engineering at Soochow University. Kosterlitz earned his PhD from the University of Oxford in 1969. He began teaching in the Department of Physics at Brown University in 1982, served as the Harrison E. Farnsworth Professor of Physics from 2006, and became an Emeritus Professor in 2026. He has long been engaged in research on condensed matter theory and statistical physics. In collaboration with David J. Thouless, he developed the Berezinskii-Kosterlitz-Thouless (BKT) theory of topological phase transitions, which revealed the mechanisms of phase transitions driven by topological defects in two-dimensional systems. This work laid an important theoretical foundation for research on two-dimensional superfluids, superconducting films, magnetic thin films, and two-dimensional melting phenomena. He has received honors such as the Maxwell Medal and the Lars Onsager Prize.
This lecture was organized by the School of Physics of NJU, the National Laboratory of Solid State Microstructures, and the Jiangsu Provincial Center for Physical Sciences Exploration. The event was packed with attendees, providing faculty and students at Nanjing University with a valuable opportunity to engage face-to-face with a Nobel laureate.
