Classification of Non-Fermi Liquids and Universal Superconducting Fluctuations

Event Date:
2026-04-09T15:00:00
2026-04-09T16:00:00
Event Location:
HENN 318
Speaker:
Professor Sung-Sik Lee (McMaster and Perimeter Institute)
Related Upcoming Events:
Theory Seminars
Intended Audience:
Everyone
Local Contact:

Fei Zhou (feizhou@phas.ubc.ca) 

Event Information:

Abstract:

Quantum critical metals host a wide variety of non-Fermi liquid states, whose properties depend on the nature of critical fluctuations 
coupled to the Fermi surface. While some of non-Fermi liquids remain stable down to zero temperature, others exhibit strong superconducting instabilities. A systematic classification of non-Fermi liquids, however, has been challenging, largely due to the absence of conventional scale invariance associated with the presence of a finite Fermi momentum. 

In this talk, I will discuss a generalized notion of renormalization group fixed points and show how it enables a unified classification of non-Fermi liquids and their superconducting instabilities. This talk is based on arXiv:2601.21047.

Bio:

Dr. Sung-Sik Lee is a Professor in the Department of Physics and Astronomy at McMaster University and an Associate Faculty member at the Perimeter Institute for Theoretical Physics, specializing in strongly interacting quantum many-body systems. His research focuses on non-Fermi liquids, quantum field theory, and emergent gravity.

Links:

Add to Calendar 2026-04-09T15:00:00 2026-04-09T16:00:00 Classification of Non-Fermi Liquids and Universal Superconducting Fluctuations Event Information: Abstract: Quantum critical metals host a wide variety of non-Fermi liquid states, whose properties depend on the nature of critical fluctuations coupled to the Fermi surface. While some of non-Fermi liquids remain stable down to zero temperature, others exhibit strong superconducting instabilities. A systematic classification of non-Fermi liquids, however, has been challenging, largely due to the absence of conventional scale invariance associated with the presence of a finite Fermi momentum.  In this talk, I will discuss a generalized notion of renormalization group fixed points and show how it enables a unified classification of non-Fermi liquids and their superconducting instabilities. This talk is based on arXiv:2601.21047. Bio: Dr. Sung-Sik Lee is a Professor in the Department of Physics and Astronomy at McMaster University and an Associate Faculty member at the Perimeter Institute for Theoretical Physics, specializing in strongly interacting quantum many-body systems. His research focuses on non-Fermi liquids, quantum field theory, and emergent gravity. Links: Perimeter Institute faculty page: https://perimeterinstitute.ca/people/sung-sik-lee   McMaster University faculty page: https://physics.mcmaster.ca/~slee/  Perimeter Institute article: "Mapping the road to quantum gravity": https://perimeterinstitute.ca/news/mapping-road-quantum-gravity  Youtube video: "Sung-Sik Lee: Emergent phenomena in quantum matter": https://www.youtube.com/watch?v=McQQi117zR8   Event Location: HENN 318