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
439 2022-07-21 16:00  CAPP Seminar Room C303, Creation Hall, KAIST Munji Campus  Quintessential axions file
438 2023-12-14 16:00  CAPP Seminar Room C303, Creation Hall, KAIST Munji Campus  Superconducting qubits for large-scale quantum computers file
437 2022-09-21 16:00  College of Natural Science E6-2, Rm. 1323  Materials and Device Nanofabrication of Optical Metasurfaces file
436 2015-03-13 14:00  Connect Room, KI Bldg.  The 15th Innovative Workshop on Soft/Bio Materials file
435 2015-12-09 11:00  E4(KI Building), Connect room (2nd fl.)  Functional Imaging & Monitoring of Brain & Breast with Diffuse Light
434 2015-12-17 11:00  E4(KI Building), Matrix Hall (2nd fl.)  Wavefront engineering for in-vivo Deep brain imaging
433 2015-07-23 13:30  E4, B401  Enhanced ZnO based UV photonics and related applications file
432 2023-04-28 11:00  E6 #1323  Tkachenko wave: From the modern field theory viewpoint
431 2023-05-17 14:00  E6 #1323  Optical Response in the multilayer thin films
430 2022-10-06 13:00  E6 #1323  Counting States with Global Symmetry
429 2022-04-13 10:30  E6 #1323/zoom  Harnessing topology and correlations from singularities in 3d-kagome metals
428 2022-01-11 15:00  E6 #1501  Ultrafast optical studies on CDW collective modes of the Weyl-CDW (TaSe4)2I file
427 2022-01-26 13:00  E6 #1501  An Introduction to Cohomology groups file
426 2022-08-01 10:00  E6 #1501 & Zoom  [Update 세미나 영상] James Webb Space Telescope & OTE Commissioning
425 2022-07-14 14:15  E6 #1501 & Zoom  Hund and electronic correlations in ruthenium-based systems
424 2022-07-14 15:00  E6 #1501 & Zoom  Pure two-dimensional quantum electron liquid and its phase transition
423 2022-07-14 13:30  E6 #1501 & Zoom  Electronic structure and anomalous transport properties of topological materials by first principle calculation
422 2022-10-24 16:00  E6 #1501(공동강의실)  Physics Colloquim(Fall 2022) file
421 2022-01-25 15:00  E6 #1501/online  Emulating twisted double bilayer graphene with a multiorbital optical lattice file
420 2022-03-31 10:00  E6 #1501/zoom  Weiss fields for Quantum Spin Dynamics file