visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-10-26 10:00 
연사  
장소 E6-2 #2502 

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 연사 제목
공지 2025-02-24 16:00    2025년 봄학기 콜로키움 안내
공지 2025-02-27 16:00    2025년 봄 물리학과 특별세미나 (광학/응집물리 분야)
374 2019-07-08 14:00    Ultrabroadband squeezed pulses and their relation to relativity file
373 2019-07-10 16:00    Public Lectures file
372 2019-07-16 16:00    2019 Physics Distinguished Lecture file
371 2019-07-21 12:00    Challenges and Opportunities in Theoretical Particle Physics 2019 file
370 2019-07-25 16:00    Band topology of twisted bilayer graphene file
369 2019-07-30 16:00    Dirac fermions and flat bands in correlated kagome metals file
368 2019-07-31 16:00    Features of ballistic superconducting graphene file
367 2019-08-01 14:00    Low-density Superconductivity in SrTiO3 Probed by Planar Tunneling Spectroscopy file
366 2019-08-06 16:00    Visualization of in-plane piezoresponse vector fields file
365 2019-08-14 16:00    Quantum Optics, at the heart of quantum metrology and quantum information file
364 2019-08-16 14:00    Multiferroic and Magnetoelectric Effects by Tailoring Interfacial Chemistry and Physics in Correlated Oxides file
363 2019-08-19 10:00    Tutorials on Multimode Quantum Optics in the Continuous Variable Regime file
362 2019-08-22 16:00    Physics and Applications in Nanoelectronics and Nonomechanics file
361 2019-08-27 16:00    Critical current properties of Fe-based superconductors file
360 2019-09-02 16:00    Fall 2019: Physics Colloquium file
359 2019-09-10 15:00    Two-Stage Kondo Effect file
358 2019-09-10 15:00    (2+1) D Duality Web from 3D Euclidean Lattice file
357 2019-09-18 16:00    Exploring Synthetic Quantum Matter in Superconducting Circuits file
356 2019-09-18 16:00    Fall 2019: Physics Seminar Serises file
355 2019-09-26 16:00    Entanglement Swapping with Autonomous Polarization-Entangled Photon-Pairs from Warm Atomic Ensemble file