visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나

Moir\’e fractals in supermoir\’e structures

2024.06.04 11:12

admin 조회 수:1546

날짜 2024-06-05 10:00 
연사  
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 2025-02-24 16:00    2025년 봄학기 콜로키움 안내
공지 2025-02-27 16:00    2025년 봄 물리학과 특별세미나 (광학/응집물리 분야)
567 2015-07-16 16:00    KAIST Physics Distinguished Lecture
566 2015-07-16 16:00    Next-generation ultrafast laser technology for nonlinear optics and strong-field physics
565 2015-07-23 13:30    Enhanced ZnO based UV photonics and related applications file
564 2015-08-03 10:30    Axion Search
563 2015-08-04 11:00    Propagation of ultrasound through two- and three-dimensional strongly scattering media
562 2015-09-07 15:00    Advanced Optical Materials and Devices at NRL
561 2015-09-07 16:00    Physics Colloquium : 2015 Fall file
560 2015-09-14 14:00    Ultrafast X-ray Studies on Dynamics Matter in Extreme Conditions
559 2015-09-15 16:00    Physics Colloquium : 2014 Fall file
558 2015-10-14 18:00    인터스텔라 영화 속의 물리 file
557 2015-10-15 10:00    Development of Large-Bore, High Field Magnets at the NHMFL
556 2015-10-16 15:00    High Magnetic Fields to Probe the sub-eV range of Particle/Astroparticle Physics - From the OSQAR experiments at CERN up to new perspectives at LNCMI-Grenoble
555 2015-10-16 16:00    Fluctuations of entropy production in partially masked electric circuits
554 2015-10-23 10:30    How to write a good scientific paper[Open lecture series]
553 2015-10-23 15:00    Development of a Rogowski Coil as a new beam position monitor
552 2015-11-06 16:30    Topological Dirac line nodes in centrosymmetric semimetals
551 2015-11-10 16:00    Rapid heating of matter using high power lasers
550 2015-11-19 16:00    Emergent Collective Phenomena and Functions at Reduced Dimensions
549 2015-11-23 13:30    What's Beyond the Standard Model? Lessons from Run I and what might come in Run II
548 2015-11-24 16:00    Topology-based understanding of spin dynamics in inhomogeneously magnetized systems