visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-10-26 10:00 
일시 Oct. 26th (Wed), 10:00AM 
장소 E6-2 #2502 
연사 Dr. Sun-woo Kim(Univ. of Cambridge) 

물리학과 세미나 안내 드립니다. 관심있는 분들의 많은 참여 부탁드립니다.

 

- Title: Replica Higher-Order Topology of Hofstadter Butterflies in Twisted Bilayer Graphene
- Speaker: Dr. Sun-woo Kim(Univ. of Cambridge)
- Date: Oct. 26th (Wed) 2022, 10:00AM,
- Place: E6-2, #2502
Abstract: 

 

The Hofstadter energy spectrum of twisted bilayer graphene is found to have recursive higher-order topological properties. We demonstrate that higher-order topological insulator (HOTI) phases, characterized by localized corner states, occur as replicas of the original HOTIs to fulfill the self-similarity of the Hofstadter spectrum. We show the existence of the exact flux translational symmetry of twisted bilayer graphene at all commensurate angles. Based on this result, we carefully identify that the original HOTI phase at zero flux is re-entrant at a half-flux periodicity, where the effective twofold rotation is preserved. In addition, numerous replicas of the original HOTIs are found for fluxes without protecting symmetries. Similar to the original HOTIs, replica HOTIs feature both localized corner states and edge-localized real-space topological markers. The replica HOTIs originate from the different interaction scales, namely, intralayer and interlayer couplings, in twisted bilayer graphene. The topological aspect of Hofstadter butterflies revealed in our results highlights symmetry-protected topology in quantum fractals.

번호 날짜 장소 제목
공지 2022-11-25 11:00  E6-2 #1323  [Update 세미나영상](응집물리 세미나) DMFT+ NRG: From models to real materials, from local to nonlocal correlations
380 2022-10-28 11:00  E6-2 #1323  [Update 세미나영상] (응집물리 세미나) Machine-Learning-Guided Prediction models and Materials discovery for high Tc cuprates file
379 2016-10-27 16:00  #1323(E6-2)  Terahertz Metal Optics
378 2022-10-27 16:00  E6-2 #1323  (광학분야 세미나) Cavity optomechanical systems for quantum transduction
» 2022-10-26 10:00  E6-2 #2502  Replica Higher-Order Topology of Hofstadter Butterflies in Twisted Bilayer Graphene
376 2019-10-25 15:00  #1323, E6-2  Physics Seminar file
375 2016-10-18 15:00  E6-2. 1st fl. #1323  “Hybrid quantum systems with mechanical oscillators”
374 2016-10-18 13:30  1st fl. #1323(E6-2)  "Visualization of oxygen vacancy in motion and the interplay with electronic conduction"
373 2016-10-17 11:00  #1323,(E6-2, 1st fl.)  IMS and examples of the studies on optoelectronic materials
372 2020-10-16 16:00  https://kaist.zoom.us/j/89198078609  Hidden room-temperature ferroelectricity in CaTiO3 revealed by a metastable octahedral rotation pattern file
371 2020-10-16 14:30  https://kaist.zoom.us/j/89198078609  Nanoscale magnetic resonance detection towards nano MRI file
370 2020-10-15 16:00  (https://kaist.zoom.us/j/93997220310)  Towards resource-efficient and fault-tolerant quantum computation with nonclassical light
369 2022-10-13 16:00  E6-2 #1323  (광학분야 세미나) Ultrafast Optics for Ultra-Precision Metrology and Realization of Flexible/Stretchable Laser-Induced-Graphene Electronics
368 2018-10-12 16:00  E6-2. 1st fl. #1323  Direct observation of a two-dimensional hole gas at oxide interfaces file
367 2018-10-12 14:30  E6-2. 1st fl. #1323  Quantum Advantage in Learning Parity with Noise file
366 2017-10-10 16:00  E6-2 #1323  Discovery of New 2D Materials with Diverse Physical Properties
365 2016-10-07 16:00  E6-2. #1323(1st fl.)  “Tilt engineering of 4d and 5d transition metal oxides?”
364 2016-10-07 13:30  E6-2. #1323(1st fl.)  “Symmetry and topology in transition metal dichalcogenide?”
363 2020-10-09 09:00  https://kaist.zoom.us/j/85161896513?pwd=U3pwWFFZaWVRamxDZUR5REhNeVk0UT09  Quantum Many-Body Simulation file
362 2020-10-23 14:00  E6-2 #1323  Plasmon spectroscopy of low-dimensional superconductors in fluctuating regime file
361 2018-11-08 16:00  #1323, E6-2  Conformality lost file