visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나

Moir\’e fractals in supermoir\’e structures

2024.06.04 11:12

admin 조회 수:7770

날짜 2024-06-05 10:00 
연사 Deepanshu Aggarwal(Physics, Indian Institute of Technology) 
장소 E6, #2501 
아래와 같이 세미나를 개최하고자 하오니, 관심있는 분들의 많은 참석 부탁드립니다.
 
Date: 10:00 am, 5th Jun (Wed)
 
Place: E6, #2501
 
Speaker: Deepanshu Aggarwal(Physics, Indian Institute of Technology)
 
Title: Moir\’e fractals in supermoir\’e structures
 
Abstract: 

Twisted bilayer graphene (TBLG) subjected to a sequence of commensurate external periodic potentials [for a detailed review, see Ref.3] results in the formation of moir\'{e} fractals (MFs) [ref. 1] that can quantitatively describe the band structure of a large class of super-moir\'{e} systems. The self-similarity of the hierarchy of Brillouin zones (BZ) in such moir\'{e} fractals so produced results in a nested subband structure inside the bandwidth of the original moiré bands, and the number of such sub-bands can be directly computed with the help of fractal dimension. The fractal generators for such MFs are derived, and we examine their effect on the BZ edge hierarchy. We also find parallels between such MFs and those arising in economic geography related to transportation and correspondence within the framework of central place theory. We point out that the concept of MF is quite general and can be easily extended to non-graphene twisted heterostructures. The modification of band structure can strongly influence correlated phase and optical properties[ ref. 2], and various other transport and thermodynamic properties in such twisted heterostructures. Recent work shows lattice relaxations significantly alter the electronic band structure of twisted, layered structures. In further work, we show the robustness of MFs in the presence of lattice distortion-induced strain field and examine whether the number of in-gap states given by the fractal dimension remains the same under such strain [4].


 [1] D Aggarwal, Rohit Narula, and Sankalpa Ghosh, "Moiré fractals in twisted graphene layers," Phys. Rev. B 109, 125302 (2024) (Editor's Suggestion) [2] Disha Arora, Deepanshu Aggarwal, Sankalpa Ghosh, and Rohit Narula, "Interference effects in polarization-controlled Rayleigh scattering in twisted bilayer graphene,"Phys. Rev. B 107, 205423 (2023) [3] Deepanshu Aggarwal, Rohit Narula, and Sankalpa Ghosh "A primer on twistronics: a massless Dirac fermion's journey to moiré patterns and flat bands in twisted bilayer graphene," J. Phys.: Condens. Matter 35 143001 (2023) (Invited Topical Review) [4] Deepanshu Aggarwal, Rohit Narula and Sankalpa Ghosh., Moir\'{e} fractals under strain, (manuscript under preparation)

 
번호 날짜 연사 제목
공지 2025-09-01 12:00    2025년 가을학기 콜로키움
공지 2025-09-05 11:00    2025년 가을학기 물리학과 특별세미나 (광학/응집물리 분야)
362 2019-06-28 13:30    Magnetic domains and domain wall conduction in pyrochlore iridate thin films and heterostructures file
361 2016-10-27 16:00    Terahertz Metal Optics
360 2016-11-18 10:30    Non-equilibrium many-body spin dynamics in diamond
359 2022-09-15 13:00    AdS black holes: a review
358 2022-05-18 16:00    Geometry, Algebra, and Quantum Field Theory
357 2022-05-19 16:00    Chasing Long Standing Neutrino Anomalies with MicroBooNE
356 2025-08-22 11:00  Dr.Joon young Choi (Kyungpook National University)  Mysterious Magnetization and Rotational Hysteresis in the magnetic torque of Co1/3TaS2 file
355 2022-05-12 16:00    New frontiers of electroweak physics at the LHC
354 2024-01-16 16:00    [High Energy Theory Seminar] Towards quantum black hole microstates
353 2024-10-21 13:00  Geonhwi Hwang (Hokkaido University)  [Physics Seminar] “Non-Hermitian Point-Gap Topology in Junction Systems” file
352 2019-12-27 15:00    The superconducting order parameter puzzle of Sr2RuO4 file
351 2019-12-27 15:00    The superconducting order parameter puzzle of Sr2RuO4 file
350 2019-09-26 16:00    Entanglement Swapping with Autonomous Polarization-Entangled Photon-Pairs from Warm Atomic Ensemble file
349 2023-11-30 10:30    [High-Energy Theory Seminar] 3d-3d correspondence and 2d N = (0,2) boundary conditions
348 2024-08-16 11:00  Hikaru Saito (Kyushu University, Japan)  Cathodoluminescence for nanophotonics: Applications to plasmonic bandgap materials and perovskite semiconductors file
347 2020-01-17 16:00    Symmetry Breaking and Topology in Superfluid 3He file
346 2019-08-27 16:00    Critical current properties of Fe-based superconductors file
345 2024-09-26 14:00  Hoon Kim (Caltech, USA)  Quantum spin nematic phase in a square-lattice iridate
344 2019-08-01 14:00    Low-density Superconductivity in SrTiO3 Probed by Planar Tunneling Spectroscopy file
343 2024-02-16 10:00  Hyeok-Jun Yang (Department of Physics, University of Notre Dame)  Optical conductivity of superconducting states driven by Van Hove singularities