visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-06-03 11:00 
일시 June 3(Fri.) 11:00 
장소 E6-2 #1323 
연사 Prof. Gil Young Cho (Department of Physics, POSTECH) 
1. Date / Time 
    - June  3, 2022
    - 11:00 AM (KST)
 
2. Place / ZOOM 
    - Room 1323, KAIST Natural Sciences Lecture Hall(E6-2) (자연과학동 1323호)
 
3. Speaker
    - Prof. Gil Young Cho (Department of Physics, POSTECH)
 
4. Talk Title
    - Theoretical Investigation of Exotic Quantum States in Low-dimensional Materials
 
5. Abstract
    -  Because of the enhanced quantum fluctuations, low-dimensional quantum materials provide a natural platform for exotic emerging phenomena. The archetypical examples include Tomonaga-Luttinger liquids, fractional quantum Hall states, and high-Tc superconductivity. More recently, several new members of exotic quantum states have been discovered in novel low-dimensional materials such as twisted van der Waals materials and 2D charge-density wave materials. 
 
       In the first part of this talk, we will primarily focus on the so-called conducting network systems, where 1D metallic wires form a periodic 2D superstructure. Such structure naturally appears in several of twisted 2D materials, and also in some charge-density wave materials [2], where domain walls form a regular 2D network superstructure. For these network systems, we first theoretically prove [1] that they realize robust flatbands, which can naturally explain the enhanced superconductivity. We also show that corner states, which are a hallmark of the higher-order topological insulators [4], appear in the network superstructure. Next, we theoretically show that a remarkably wide variety of new non-Fermi liquids emerge and that these non-Fermi liquids can be classified by the characteristics of the junctions in networks [3]. Using this, we calculate the electric conductivity of the non-Fermi liquids as a function of temperature, which show markedly different scaling behaviors than a regular 2D Fermi liquid. 
 
        If time allows, we will also discuss the future research and present their perspectives, which include the experimental recipes for the realization and theoretical characterization of steady Floquet states [5] and the classification of quantum phases of matter.   
 

References 

[1] J. Lee, C. Geng, J. Park, M. Oshikawa, S. Lee, H. Yeom, and GYC*, Physical Review Letters (2019)

[2] J. Park, GYC, J. Lee, and H. Yeom*, Nature Communications (2019) 

[3] J. Lee, M. Oshikawa, and GYC*, Physical Review Letters (2021)

[4] B. Kang, W. Lee, and GYC*, Physical Review Letters (2021) 

[5] S. Park, W. Lee, S. Jang, Y. Choi, J. Park, W. Jung, K. Watanabe, T. Taniguchi, GYC*, G. Lee*, Nature (2022)

번호 날짜 장소 제목
259 2015-12-03 16:00  E6-2, #1323  Hybrid solid state spin qubits in wide bandgap semiconductors
258 2015-11-24 16:00  E6-2, #1323  Topology-based understanding of spin dynamics in inhomogeneously magnetized systems
257 2015-11-23 13:30  E6-2, #1323  What's Beyond the Standard Model? Lessons from Run I and what might come in Run II
256 2015-11-28 10:00  E6-2, #1323  Electron Tunneling Spectroscopy of Single and Bilayer Graphene with Hexagonal Boron Nitride as Tunneling Barrier
255 2015-12-01 16:00  E6-2, #1323  Introducing extra dimensions to spectroscopic studies of advanced quantum materials
254 2015-12-11 13:30  E6-2, #1323  Quantum spin liquid in the 1/3 depleted triangular lattice Ba3(Ru1-xIrx)Ti2O9
253 2015-12-11 15:45  E6-2, #1323  Dynamical mean field theory studies on heavy fermion system
252 2016-01-11 16:00  E6-2, #1323  Mott Physics in the Strong Spin-Orbit Coupling Regime
251 2016-01-26 14:00  E6-2, #1323  Electrochemistry on Nano- and Atomic Levels: Scanning Probe Microscopy Meets Deep Data
250 2016-09-29 16:00  E6-2, #1323  2016 Fall, Physics Seminar Serises file
249 2019-06-24 11:00  E6-2, #1323  Topological photonic anomalies file
248 2019-07-25 16:00  E6-2, #1323  Band topology of twisted bilayer graphene file
247 2019-07-31 16:00  E6-2, #1323  Features of ballistic superconducting graphene file
246 2022-09-15 13:00  E6-2, #1323  AdS black holes: a review
245 2023-07-12 11:00  E6-2, #1323  Study of spin-1/2 antiferromagnetic kagome Heisenberg model by symmetric projected entangled simplex states
244 2023-07-11 11:00  E6-2, #1323  Ordered phases, non-Fermi liquid, and quantum criticality driven by entanglement between multipoles and conduction electrons
243 2023-07-19 16:00  E6-2, #1323  [High-Energy Theory Seminar]Deriving the Simplest Gauge-String Duality
242 2023-07-18 11:00  E6-2, #1323  Non-Hermitian Casimir Effect of Magnons
241 2023-12-19 16:00  E6-2, #1323  [High Energy Theory Seminar] Non-invertible symmetries, leptons, quarks, and why multiple generations
240 2024-01-03 11:00  E6-2, #1323  Interplay of Strong Correlations, Topology, and Disorder in 2D Quantum Matters