Sung-Sik Lee

Research Interests

Condensed matter systems, that include insulators, semiconductors, metals and superconductors among many others, consist of many particles, of the order of ten to the twenty three. At the microscopic level, the dynamics of individual particles is governed by the well established theoretical framework, quantum mechanics. However, it is extremely difficult to understand and predict macroscopic behaviors of a whole system, starting from the microscopic theory. For the past 30 years, it has become clear that understanding macroscopic properties is not a matter of mere application of the known physical laws. Instead, collective behaviors are governed by novel organizing principles, which are not manifest at all from the microscopic rule of dynamics. Currently, the primary goal of my research is to identify new dynamical principles that are behind novel emergent phenomena in gapless phases of matter such as unconventional metals and systems near quantum critical points, and to apply those principles to understand physical properties observed in experiments. To achieve the goal, I use various theoretical tools, including quantum many-body theory and quantum field theory. I am also interested in the interdisciplinary research areas between condensed matter physics, string theory and gravitational theory. Recently I have been developing the notion of `quantum renormalization group' where coupling constants are promoted to quantum mechanical operators to make a connection between general D-dimensional quantum many-body systems and (D+1)-dimensional quantum theory of gravity via holography.

Positions Held

• July 2012 - present : Department of Physics and Astronomy, McMaster University, Associate Professor
• July 2007 - June 2012 : Department of Physics and Astronomy, McMaster University, Assistant Professor
• July 2006 --- June 2007 : Post doctoral researcher, Kavli Institute for Theoretical Physics, Santa Barbara
• Mar. 2004 --- Jul. 2006 : Post doctoral researcher, Massachusetts Institute of Technology
• Nov. 2002 --- Feb. 2004: Post doctoral researcher, Pohang University of Science and Technology

Awards

• Early Research Award, $100,000 for five years, Ontario Ministry of Research and Innovation

Recent Publications

• Marlon Rodney, H. Francis Song, Sung-Sik Lee, Karyn Le Hur, Erik Sorensen, "Scaling of entanglement entropy across Lifshitz transitions", Phys. Rev. B 87, 115132 (2013)
• Sung-Sik Lee, "Background independent holographic description : From matrix field theory to quantum gravity", JHEP 1210 (2012) 160
• S.-S. Lee, ``Holographic Matter : Deconfined String at Criticality'', Nucl. Phys. B 862, 781 (2012), arXiv: 1108.2253.
• S. Bhattacharjee, S.-S. Lee and Y. B. Kim, ``Spin-Orbital Locking, Emergent Pseudo-Spin, and Magnetic order in Na2IrO3'', New J. Phys.14, 073015 (2012), arXiv: 1108.1806.
• S. Bhattacharjee, Y. B. Kim, S.-S. Lee, and D.-H. Lee, ``Fractionalized topological insulators from frustrated spin models in three dimensions'', Phys. Rev. B 85, 224428 (2012), arXiv: 1202.0291.
• S. Ghamari, C. Kallin, S.-S. Lee, and E. S. Sorensen, ``Order in a Spatially Anisotropic Triangular Antiferromagnet'', Phys. Rev. B 84, 174415 (2011), arXiv : 1108.3036.
• S.-S. Lee, ``Holographic description of large N gauge theory'', Nucl. Phys. B 851, 143 (2011), arXiv: 1011.1474.
• Denis Dalidovich and Sung-Sik Lee, "Perturbative non-Fermi liquids from dimensional regularization", arXiv: 1307.3170
• Sung-Sik Lee, "Quantum Renormalization Group and Holography", arXiv: 1305.3908.
• P. Ponte and S.-S. Lee, ``Emergence of supersymmetry on the surface of three dimensional topological insulators'', arXiv : 1206.2340

Seminars

• "Quantum renormalization group and Holography", Workshop and Conference on Geometrical Aspects of Quantum States in Condensed Matter, ICTP, Trieste, Italy, July 2013
• "Low energy effective theories for non-Fermi liquids in two dimensions", Bad metal behavior and Mott quantum criticality, APCTP, Pohang, Korea, July 2013
• "Quantum renormalization group and AdS/CFT", String Seminar, Caltech, April 2013
• "Quantum renormalization group and AdS/CFT", String Seminar, University of Michigan, Ann Abor, March 2013
• "Quantum renormalization group and AdS/CFT", Simons Symposium on Quantum Entanglement, Caneel Bay, St. John, Feb. 2013
• "From renormalization group to emergent gravity: holographic description of quantum many-body matter", String Seminar, MIT, Nov. 2012
• "From renormalization group to emergent gravity: holographic description of quantum many-body matter", Topology, Entanglement and Strong Correlations in Condensed Matter, University of Urbana Champaign, Nov. 2012
• "Emergent phenomena in condensed matter systems", Colloquium, Virginia Tech, Nov. 2012
• "From Renormalization Group to Emergent Gravity: Holographic Description of Quantum Many-body Systems", KITP Conference: Exotic Phases of Frustrated Magnets, KITP, Santa Barbara, Oct. 2012
• "Chiral non-Fermi liquids in two dimensions", Center for Quantum Materials Inaugural conference, Field Institute, Toronto, Sep. 2012
• "From renormalization group to emergent gravity: holographic description of quantum many-body systems", ICTP2012: Innovations in Strongly Correlated Electronic Systems, ICTP, Trieste, Italy, August 2012
• ``Non-Fermi liquids in two dimensions'', 2012 Canadian Association of Physicists Congress, Alberta, June 2012
• ``Quantum field theory and quantum gravity'', Theoretical Physics Workshop, University of Western Ontario, April 2012
• ``Emergent dimension and quantum critical point'', APS March meeting, Boston, March 2012
• ``Holographic matter; deconfined string at criticality", SPOCK meeting, University of Cincinnati, December 2011
• ``Holographic matter; deconfined string at criticality'', String Seminar, University of California, Berkeley, Nov. 2011
• ``Connections between new states of condensed matter and string'', Origins Colloquium, Origin Institute, McMaster University, Oct. 2011
• ``Holographic matter; deconfined string at criticality", Holographic Duality and Condensed Matter Physics, KITP, Santa Barbara, USA, September 2011
• ``Holographic matter; deconfined string at criticality", KIAS-YITP Joint Workshop on String Theory, Holography and Beyond, Seoul, Korea, September 2011
• ``Holographic matter; deconfined string at criticality", Conference on Cold Materials, Hot Nuclei, and Black Holes: Applied Gauge/Gravity Duality, ICTP, Trieste, Italy, August 2011
• ``Holographic Matter'', Workshop on Emergence in Field Theory, IAS, Nanyang Technological University, Singapore, Aug 2011
• PIRSA:12060028, TBA, 2012-06-08, Exploring AdS/CFT Dualities in Dynamical Settings
• PIRSA:12050033, Background Independent Holographic Description : From Matrix Field Theory to Quantum Gravity, 2012-05-22, String Seminars
• PIRSA:11100095, First Principle Construction of Holographic Duals , 2011-10-25, Tensor Networks for Quantum Field Theories Conference
• PIRSA:11100057, Quantum Order and Emergent Space in Holographic Phases of Matter, 2011-10-18, String Seminars
• PIRSA:10070001, Holographic description of quantum field theory, 2010-07-20, String Seminars
• PIRSA:10050087, Holographic description of quantum field theory, 2010-05-29, Emergence and Entanglement
• PIRSA:08120018, Emergent supersymmetry and holographic non-Fermi liquid , 2008-12-03, String Seminars
• PIRSA:07040033, Spin Liquid with Spinon Fermi Surface: Its Stability and Possible Application to the Organics, 2008-04-24, Southwestern Ontario 4-Corner Condensed Matter Symposium