Results 21 to 30 of about 10,146 (239)

Enhanced third-harmonic generation by manipulating the twist angle of bilayer graphene

Light: Science & Applications, 2021
Nonlinear optics: When graphene ‘does the twist’ Modifying the angle between the two layers of twisted bilayer graphene can considerably improve how photons interact with it to generate higher-energy photons.
Seongju Ha, Nam Hun Park, Hyeonkyeong Kim, Jiseon Shin, Jungseok Choi, Sungmin Park, Ji-Yun Moon, Kwanbyung Chae, Jeil Jung, Jae-Hyun Lee, Youngdong Yoo, Ji-Yong Park, Kwang Jun Ahn, Dong-Il Yeom   +13 more
doaj   +1 more source

Realization of topological Mott insulator in a twisted bilayer graphene lattice model

Nature Communications, 2021
Magic-angle twisted bilayer graphene exhibits a quantum anomalous Hall effect at 3/4 filling; however, its mechanism is debated. Here, the authors show that such a phase can be realized in a lattice model of twisted bilayer graphene in the strong ...
Bin-Bin Chen, Yuan Da Liao, Ziyu Chen, Oskar Vafek, Jian Kang, Wei Li, Zi Yang Meng   +6 more
doaj   +1 more source

Topological piezoelectric response in moiré graphene systems

Physical Review Research, 2022
We theoretically study the piezoelectric effects in moirè graphene systems. Since the strain couples to the electrons in the system as an effective vector field, which has opposite signs for the K and K^{′} valleys of graphene, its effects on the two ...
Ran Peng, Jianpeng Liu
doaj   +1 more source

Understanding symmetry breaking in twisted bilayer graphene from cluster constraints

Physical Review Research, 2023
Twisted bilayer graphene is an exciting platform for exploring correlated quantum phases, extremely tunable with respect to both the single-particle bands and the interaction profile of electrons. Here, we investigate the phase diagram of twisted bilayer
Nikita Astrakhantsev, Glenn Wagner, Tom Westerhout, Titus Neupert, Mark H. Fischer   +4 more
doaj   +1 more source

Intrinsic superflat bands in general twisted bilayer systems

Light: Science & Applications, 2022
Twisted bilayer systems with discrete magic angles, such as twisted bilayer graphene featuring moiré superlattices, provide a versatile platform for exploring novel physical properties.
Hongfei Wang, Shaojie Ma, Shuang Zhang, Dangyuan Lei   +3 more
doaj   +1 more source

Cascade of transitions in twisted and non-twisted graphene layers within the van Hove scenario

npj Quantum Materials, 2022
Motivated by measurements of compressibility and STM spectra in twisted bilayer graphene, we analyze the pattern of symmetry breaking for itinerant fermions near a van Hove singularity. Making use of an approximate SU(4) symmetry of the Landau functional,
Dmitry V. Chichinadze, Laura Classen, Yuxuan Wang, Andrey V. Chubukov   +3 more
doaj   +1 more source

Correlated states in twisted double bilayer graphene [PDF]

, 2020
Electron-electron interactions play an important role in graphene and related systems and can induce exotic quantum states, especially in a stacked bilayer with a small twist angle. For bilayer graphene where the two layers are twisted by a "magic angle",
Chu, Yanbang, Li, Na, Liu, Jieying, Meng, Zi Yang, Shen, Cheng, Shi, Dongxia, Tang, Jian, Taniguchi, Takashi, Tian, Jinpeng, Wang, Shuopei, Watanabe, Kenji, Wu, QuanSheng, Yang, Rong, Yazyev, Oleg V., Zhang, Guangyu, Zhao, Yanchong   +15 more
core   +2 more sources

Spontaneous time-reversal symmetry breaking in twisted double bilayer graphene

Nature Communications, 2022
Twisted double bilayer graphene (tDBG) comprises two Bernal-stacked bilayer graphene sheets with a twist between them. Here, the authors report a strong anomalous Hall effect in the correlated-metal regime of tDBG, indicating time reversal symmetry ...
Manabendra Kuiri, Christopher Coleman, Zhenxiang Gao, Aswin Vishnuradhan, Kenji Watanabe, Takashi Taniguchi, Jihang Zhu, Allan H. MacDonald, Joshua Folk   +8 more
doaj   +1 more source

Strong electron-phonon coupling in magic-angle twisted bilayer graphene. [PDF]

Nature
Chen C, Nuckolls KP, Ding S, Miao W, Wong D, Oh M, Lee RL, He S, Peng C, Pei D, Li Y, Hao C, Yan H, Xiao H, Gao H, Li Q, Zhang S, Liu J, He L, Watanabe K, Taniguchi T, Jozwiak C, Bostwick A, Rotenberg E, Li C, Han X, Pan D, Liu Z, Dai X, Liu C, Bernevig BA, Wang Y, Yazdani A, Chen Y.   +33 more
europepmc   +2 more sources

Fractional Chern insulators in magic-angle twisted bilayer graphene. [PDF]

Nature, 2021
Xie Y, Pierce AT, Park JM, Parker DE, Khalaf E, Ledwith P, Cao Y, Lee SH, Chen S, Forrester PR, Watanabe K, Taniguchi T, Vishwanath A, Jarillo-Herrero P, Yacoby A.   +14 more
europepmc   +2 more sources