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
266 2018-07-27 15:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Muon g-2 in the 2HDM and MSSM: comprehensive numerical analysis and absolute maxima file
265 2019-07-30 16:00  #1323, E6-2  Dirac fermions and flat bands in correlated kagome metals file
264 2019-07-31 16:00  E6-2, #1323  Features of ballistic superconducting graphene file
263 2019-07-08 14:00  E6, #1322  Ultrabroadband squeezed pulses and their relation to relativity file
262 2018-07-09 14:00  #1323, E6-2  The principles of collective learning file
261 2017-07-14 15:00  #1323 (E6-2. 1st fl.)  Chiral anomaly in disordered Weyl semimetals file
260 2016-06-01 16:00  #1323(E6-2 1st fl.)  Laboratory experiments relevant to mesospheric clouds, Saturn’s rings & astrophysical jets
259 2023-06-22 16:00  E6-2,1323  [High Energy Physics Seminar] The Branes Behind Generalized Symmetry Operators
258 2021-06-22 17:00  Zoom webinar  Spintronics meets Quantum Materials file
257 2019-06-24 11:00  E6-2, #1323  Topological photonic anomalies file
256 2019-06-28 14:00  E6-2, #1322  1st Research-exchange meeting of computational material physics file
255 2021-06-08 10:00  Zoom webinar  Photonic crystal devices for sensing file
254 2018-06-01 11:00  E6-2. 1st fl. #1323  Topological phases in low-dimensional quantum materials file
253 2023-06-01 16:00  E6-2 #1323  (광학분야 세미나)Quantum sensing using a squeezed light from hot Rb vapor
252 2016-06-01 10:30  BK21 Conference Room (#1318, E6-2)  Welcome to Nature Photonics
251 2022-06-10 14:30  E6-2. 1st fl. #1323  Combinatorial strategy for condensed matter physics: study on rare earth hexaborides thin films file
250 2022-06-10 16:00  E6-2. 1st fl. #1323  Fe5GeTe2의 나선형 자성특성과 자기저항의 전류밀도 의존성 연구 file
249 2022-06-10 11:00  Online seminar  Record-quality two-dimensional electron systems file
248 2021-06-11 14:30  Online seminar  Engineering sound waves and vibrations in multi-mode nanomechanical systems file
247 2021-06-11 16:00  Online seminar  Pseudogap in surface-doped black phosphorus file