English
Related papers

Related papers: Phonons in magic-angle twisted bilayer graphene

200 papers

We develop a theoretical framework for probing moir\'e phonon modes using Raman spectroscopy, and illustrate it with the example of twisted bilayer graphene (TBG). These moir\'e phonons arise from interlayer sliding motion in twisted 2D…

Strongly Correlated Electrons · Physics 2025-06-24 Vitor Dantas , Héctor Ochoa , Rafael M. Fernandes , Natalia B. Perkins

Flat electronic bands, characteristic of magic-angle twisted bilayer graphene (TBG), host a wealth of correlated phenomena. Early theoretical considerations suggested that, at the magic angle, the Dirac velocity vanishes and the entire…

Magic-angle twisted bilayer graphene (MATBG) exhibits a range of correlated phenomena that originate from strong electron-electron interactions. These interactions make the Fermi surface highly susceptible to reconstruction when $ \pm 1,…

Interactions among electrons and the topology of their energy bands can create novel quantum phases of matter. Most topological electronic phases appear in systems with weak electron-electron interactions. The instances where topological…

Mesoscale and Nanoscale Physics · Physics 2020-12-25 Kevin P. Nuckolls , Myungchul Oh , Dillon Wong , Biao Lian , Kenji Watanabe , Takashi Taniguchi , B. Andrei Bernevig , Ali Yazdani

Twisted bilayer graphene (TBG) near the magic twist angle of $\sim1.1^{o}$ exhibits a rich phase diagram. However, the interplay between different phases and their dependence on twist angle is still elusive. Here, we explore the stability…

Recently, the twist-angle effect on 2D van der Walls (vdW) materials, such as bilayer graphene, has attracted great attention. Many novel electronic, magnetic and even optical properties induced by such effect have been discovered. However,…

Mesoscale and Nanoscale Physics · Physics 2023-12-20 H. F. Feng , B. Liu , Zhi-Xin Guo

Recent research on twisted bilayer graphene (TBG) uncovered that its twist-angle-dependent electronic structure leads to a host of unique properties, such as superconductivity, correlated insulating states, and magnetism. The flat bands…

Mesoscale and Nanoscale Physics · Physics 2021-03-29 Adithya Kommini , Zlatan Aksamija

Magic-angle twisted bilayer graphene (MATBG) is notable as a highly tunable platform for investigating strongly correlated phenomena such as high-$T_c$ superconductivity and quantum spin liquids, due to easy control of doping level through…

Mesoscale and Nanoscale Physics · Physics 2020-06-04 Xiao Chen , Shuanglong Liu , James N Fry , Hai-Ping Cheng

Flat band electronic modes are responsible for superconductivity in twisted bilayer graphene (TBG) rotated at magic angles. From there other magic angles can be found for any multilayered twisted graphene systems. Eventually, this lead to…

Mesoscale and Nanoscale Physics · Physics 2022-12-15 Leonardo A. Navarro-Labastida , Gerardo G. Naumis

Magic-angle twisted bilayer graphene (MtBLG) has proven to be an extremely promising new platform to realize and study a host of emergent quantum phases arising from the strong correlations in its narrow bandwidth flat band. In this regard,…

We show that the electronic structure of the low-energy bands in the small angle-twisted bilayer graphene consists of a series of semi-metallic and topological phases. In particular we are able to prove, using an approximate low-energy…

Mesoscale and Nanoscale Physics · Physics 2019-07-24 Zhida Song , Zhijun Wang , Wujun Shi , Gang Li , Chen Fang , B. Andrei Bernevig

Twisted bilayer graphene displays many fascinating properties that can be tuned by varying the relative angle (also called twist angle) between its monolayers. As a remarkable feature, both the electronic flat bands and the corresponding…

Materials Science · Physics 2022-05-06 V. Hung Nguyen , Trinh X. Hoang , J. -C. Charlier

Twisted bilayer graphene (tBLG) has recently emerged as a platform for hosting correlated phenomena, owing to the exceptionally flat band dispersion that results near interlayer twist angle $\theta\approx1.1^\circ$. At low temperature a…

Strongly Correlated Electrons · Physics 2019-10-03 H. Polshyn , M. Yankowitz , S. Chen , Y. Zhang , K. Watanabe , T. Taniguchi , C. R. Dean , A. F. Young

Twisted bilayer graphene (TBG) develops large moir\'e patterns at small twist angles with flat energy bands hosting domes of superconductivity. The large system size and intricate band structure have however hampered investigations into the…

Superconductivity · Physics 2022-07-19 Tomas Löthman , Johann Schmidt , Fariborz Parhizgar , Annica M. Black-Schaffer

The salient property of the electronic band structure of twisted bilayer graphene (TBG), at the so-called magic angle (MA), is the emergence of flat bands around the charge neutrality point. These bands are associated with the observed…

Mesoscale and Nanoscale Physics · Physics 2023-09-04 Sonia Haddad , Takeo Kato , Jihang Zhu , Lassaad Mandhour

Twisted bilayer graphene with tiny rotation angles have drawn significant attention due to the observation of the unconventional superconducting and correlated insulating behaviors. In this paper, we employ a full tight-binding model to…

Mesoscale and Nanoscale Physics · Physics 2021-03-24 Xueheng Kuang , Zhen Zhan , Shengjun Yuan

We investigate magnetic instabilities in charge-neutral twisted bilayer graphene close to so-called "magic angles" using a combination of real-space Hartree-Fock and dynamical mean-field theories. In view of the large size of the unit cell…

Strongly Correlated Electrons · Physics 2021-12-08 Javad Vahedi , Robert Peters , Ahmed Missaoui , Andreas Honecker , Guy Trambly de Laissardière

Twisted bilayer graphene (tBLG) devices with ion gel gate dielectrics are studied using Raman spectroscopy in the twist angle regime where a resonantly enhanced G band can be observed. We observe prominent splitting and intensity quenching…

Mesoscale and Nanoscale Physics · Physics 2015-02-18 Ting-Fung Chung , Rui He , Tai-Lung Wu , Yong P. Chen

We theoretically investigated phonon dispersion in AA-stacked, AB-stacked and twisted bilayer graphene with various rotation angles. The calculations were performed using the Born-von-Karman model for the intra-layer atomic interactions and…

Mesoscale and Nanoscale Physics · Physics 2013-07-19 Alexandr I. Cocemasov , Denis L. Nika , Alexander A. Balandin

Graphene moire superlattices are outstanding platforms to study correlated electron physics and superconductivity with exceptional tunability. However, robust superconductivity has been measured only in magic-angle twisted bilayer graphene…

Mesoscale and Nanoscale Physics · Physics 2021-10-20 Young Woo Choi , Hyoung Joon Choi