visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-01-25 15:00 
일시 Jan. 25th (Tue), 15:00 
장소 E6 #1501/online 
연사 Junhyun Lee (Rutgers, the State University of New Jersey) 

 

Physics Seminar

 

 

 

 

Emulating twisted double bilayer graphene with a multiorbital optical lattice

 

 

Junhyun Lee

Department of Physics and Astronomy,

Rutgers, the State University of New Jersey

 

Jan. 25th (Tue), 15:00, E6 #1501/online

https://us02web.zoom.us/j/84917344494?pwd=ZlBaNWNhVlYwYUY5RnRoQ2Q2MWp0dz09

회의 ID:  849 1734 4494

암호: 890800

 

We theoretically explores how to emulate twisted double bilayer graphene with ultracold atoms in multiorbital optical lattices. In particular, the quadratic band touching of Bernal stacked bilayer graphene is emulated using a square optical lattice with px, py, and dx2y2 orbitals on each site, while the effects of a twist are captured through the application of an incommensurate potential. The quadratic band touching is stable until the system undergoes an Anderson like delocalization transition in momentum space, which occurs concomitantly with a strongly renormalized single particle spectrum inducing flat bands, which is a generalization of the magic-angle condition realized in Dirac semimetals. The band structure is described perturbatively in the quasiperiodic potential strength, which captures miniband formation and the existence of magic-angles that qualitatively agrees with the exact numerical results in the appropriate regime. We identify several magic-angle conditions that can either have part or all of the quadratic band touching point become flat. In each case, these are accompanied by a diverging density of states and the delocalization of plane wave eigenstates. It is discussed how these transitions and phases can be observed in ultracold atom experiments.

 

Contact: Eunjung Jo, (jojo@kaist.ac.kr)

 

Department of Physics, KAIST

 

번호 날짜 장소 제목
191 2018-10-25 16:00  #1323, E6-2  Abelian and non-Abelian dark photons file
190 2018-10-24 10:30  E6-1, Lecture Room 1501(1F)  Photonic integration of next-generation clocks and Hertz-absolute-accuarcy optical frequenncy synthesizers file
189 2018-10-19 10:00  #1323, E6-2  Energy conversion processes during magnetic reconnection in a laboratory plasma file
188 2018-10-18 16:00  #1323, E6-2  Applications of nonlinear optics for condensed matter researches file
187 2018-10-18 10:00  #1323, E6-2  Understanding membrane protein folding using single-molecule force techniques file
186 2018-10-16 10:00  #1323, E6-2  Capturing protein cluster dynamics and gene expression output in live cells file
185 2018-10-15 16:00  #1323, E6-2  Universal properties of macroscopic current-carrying systems file
184 2018-10-12 16:00  E6-2. 1st fl. #1323  Direct observation of a two-dimensional hole gas at oxide interfaces file
183 2018-10-12 14:30  E6-2. 1st fl. #1323  Quantum Advantage in Learning Parity with Noise file
182 2018-10-11 16:00  #1323, E6-2  Dirac electrons in a graphene quasicrystal file
181 2018-10-04 16:00  #1323, E6-2  Engineering light absorption in an ultrathin semiconductor metafilm file
180 2018-09-20 16:00  #1323, E6-2  Toward Cancer Treatment Using Terahertz Radiation: Demethylation of Cancer DNA file
179 2018-09-07 15:00  학술문화관 (E9), 2층 양승택 오디토리움  Recent developments in density functional theory: From new functionals to the nature of the chemical bond file
178 2018-09-05 16:00  #1323, E6-2  Shining a light on fractional excitations file
177 2018-09-04 14:30  E6-2. 2st fl. #2502  Ultrafast time- and angle-resolved photoemission spectroscopy (tr-ARPES) with extreme ultraviolet laser pulses file
176 2018-08-01 11:00  양분순 빌딩 (E16-1) 207호  Future of AI: Is the brain a computer? file
175 2018-07-27 15:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Muon g-2 in the 2HDM and MSSM: comprehensive numerical analysis and absolute maxima file
174 2018-07-27 13:30  #1323, E6-2  Magnetic reversal of artificial spin ice file
173 2018-07-26 14:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Inflation in String Theory and Backreaction file
172 2018-07-13 14:00  Room 5318, KAIST Natural Sciences Lecture Hall(E6).  Loop Induced Single Top Partner Production and Decay at the LHC