• HOME
  • >
  • 소식
  • >
  • 세미나
장소 E6-2 #1323 
일시 June 3(Fri.) 11:00 
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.   


[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 일시 장소 연사 제목
156 2014/12/22, 2PM  E6, Rm1319  Prof. Changbong Hyeon (KIAS)  Dynamics of molecular motors: Power stroke vs Brownian ratchet file
155 May. 3 (Fri), 11:00 AM  E6-2. 2st fl. #2502  Prof. Changhee Sohn  Exotic Magnetism file
154 2015/03/04, 12PM  1323호, E6-2  Prof. Choi Hak-Soo(Harvard)  Bioimaging and Biosensing Using Near-Infrared Fluorescence file
153 2016/03/07-06/13  E6, 1501  Prof. David Helfman(KAIST) 외  Physics Colloquium : 2016 Spring file
152 2019/09/18 - 12/5  Seminar Room #1323  Prof. David Schuster and etc.  Fall 2019: Physics Seminar Serises file
151 February 21 (Thu.), 16:00 PM  #5313, E6-2  Prof. Diptimoy Ghosh  B-meson charged current anomalies - Theoretical status file
» June 3(Fri.) 11:00  E6-2 #1323  Prof. Gil Young Cho (Department of Physics, POSTECH)  (응집물리 세미나) Theoretical Investigation of Exotic Quantum States in Low-dimensional Materials
149 October 15, 2020 (Thursday  CAPP Seminar Room #C303, Creation Hall (3F), KAIST Munji Campus  Prof. Gil-Ho Lee (POSTECH)  Graphene-based Josephson junction microwave bolometer file
148 2015/07/23,1:30PM  E4, B401  Prof. Gilles Lérondel (Univ. of Technology of Troyes)  Enhanced ZnO based UV photonics and related applications file
147 May 27,(Fri), 11:00 AM  Online seminar  Prof. Gray Rybka(University of Washington)  Current Status and Future Plans of ADMX file
146 May 31 (Fri.), 11:00 AM  #1323, E6-2  Prof. Guido Burkard  Cavity QED with Spin Qubits file
145 AUG. 31 (Thu.), 2 PM  #5318(E6-2. 5th fl.)  Prof. Hiroaki Ishizuka (The University of Tokyo)  “Berry phase and nonlinear response: photocurrent in noncentrosymmetric insulators and Weyl semimetals” file
144 DEC. 11 (Tue), 04:00 PM  E6-2. 1st fl. #1323  Prof. Hiroshi Shinaoka  Natural compact representation of Matsubara Green’s functions: applications to analytic continuation and quantum many-body simulations file
143 July 13, 2018 at 14:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Prof. Ian Lewis (The University of Kansas, Department of Physics & Astronomy)  Loop Induced Single Top Partner Production and Decay at the LHC
142 Oct 23 (Fri.), 14:00 PM  E6-2 #1323  Prof. Ivan Savenko (University of Science and Technology & IBS PCS)  Plasmon spectroscopy of low-dimensional superconductors in fluctuating regime file
141 May 29 (Tue.), 04:00 PM  #1323, E6-2  Prof. Jae-Won Jang  Investigation on metal nanostructure/semiconductor junction and its applications file
140 November 7 (Thu.), 16:00 PM  #1323, E6-2  Prof. Je-Hyung Kim  Integrated quantum photonics with solid-state quantum emitters file
139 Dec. 15 (Fri.), 9:20 AM  E6-2, Lecture Room #1323  Prof. Jhinhwan Lee 외 9명  Workshop on Magnetism in Unconventional Superconductors 개최 file
138 November 14 (Thu.), 16:00 PM  #1323, E6-2  Prof. Ji-Hun Kang  Semi-classical model of polariton propagation file
137 July 21, 2022 (Thu) 4:00 PM(KST)  CAPP Seminar Room C303, Creation Hall, KAIST Munji Campus  Prof. Jihn E. Kim (Kyoung Hee University)  Quintessential axions file