English
Related papers

Related papers: Magic-angle Bilayer Phononic Graphene

200 papers

Twisted bilayer graphene (TBG) features strongly correlated and topological phases due to its flat bands emerging near the magic angle. However, the effects of the non-Hermiticity, arising from the coupling to the environment and…

Mesoscale and Nanoscale Physics · Physics 2025-06-06 Juan Pablo Esparza , Vladimir Juricic

We derive a simple formula for the real-space chirality of twisted bilayer graphene that can be related to the cross-product of its sheet currents. This quantity shows well-defined plateaus for the first remote band as function of the gate…

Mesoscale and Nanoscale Physics · Physics 2020-09-02 T. Stauber , J. González , G. Gómez-Santos

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

The importance of phonons in the strong correlation phenomena observed in twisted bilayer graphene (TBG) at the so-called magic-angle is under debate. Here we apply gate-dependent micro-Raman spectroscopy to monitor the G band linewidth in…

Moir\'e superlattices in the twisted bilayer graphene provide an unprecedented platform to investigate a wide range of exotic quantum phenomena. Recently, the twist degree of freedom has been introduced into various classical wave systems,…

Mesoscale and Nanoscale Physics · Physics 2021-12-01 Weixuan Zhang , Deyuan Zou , Qingsong Pei , Wenjing He , Houjun Sun , Xiangdong Zhang

The interfacial coupling between electrons and magnons in adjacent layers can mediate an attractive electron-electron interaction and induce superconductivity. We consider magic-angle twisted bilayer graphene sandwiched between two…

Superconductivity · Physics 2023-01-20 Bjørnulf Brekke , Asle Sudbø , Arne Brataas

Using scanning probe microscopy and spectroscopy, we explore the spatial symmetry of the electronic wavefunctions of twisted bilayer graphene at the "magic angle" of 1.1 degrees. This small twist angle leads to a long wavelength moir\'e…

Mesoscale and Nanoscale Physics · Physics 2020-08-12 Zhiming Zhang , Rachel Myers , Kenji Watanabe , Takashi Taniguchi , Brian J. LeRoy

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

We implement a self-consistent Hartree-Fock approximation based on a microscopic model in real space, which allows us to consider the interplay between the Hubbard and the extended Coulomb interaction in twisted bilayer graphene at the…

Mesoscale and Nanoscale Physics · Physics 2021-09-15 J. Gonzalez , T. Stauber

In the past two years, magic-angle twisted bilayer graphene has emerged as a uniquely versatile experimental platform that combines metallic, superconducting, magnetic and insulating phases in a single crystal. In particular the ability to…

Mesoscale and Nanoscale Physics · Physics 2021-07-30 Folkert K. de Vries , Elias Portoles , Giulia Zheng , Takashi Taniguchi , Kenji Watanabe , Thomas Ihn , Klaus Ensslin , Peter Rickhaus

Flat band electronic modes in twisted graphene bilayers are responsible for superconducting and other highly correlated electron-electron phases. Although some hints were known of a possible connection between the quantum Hall effect and…

Mesoscale and Nanoscale Physics · Physics 2023-05-10 Leonardo A. Navarro-Labastida , Gerardo G. Naumis

Extensive investigations on the Moir\'e magic-angle have been conducted in twisted bilayer graphene, unlocking the mystery of unconventional superconductivity and insulating states. In analog to magic angle, here we demonstrate the new…

Mesoscale and Nanoscale Physics · Physics 2024-07-24 Qingxiang Ji , Bohan Li , Johan Christensen , Changguo Wang , Muamer Kadic

Twisted bilayer graphene (tBLG) provides us with a large rotational freedom to explore new physics and novel device applications, but many of its basic properties remain unresolved. Here we report the synthesis and systematic Raman study of…

The chiral Hamiltonian for twisted graphene bilayers is written as a $2\times2$ matrix operator by a renormalization of the Hamiltonian that takes into account the particle-hole symmetry. This results in an effective Hamiltonian with an…

Mesoscale and Nanoscale Physics · Physics 2023-08-01 Gerardo G. Naumis , Leonardo A. Navarro-Labastida , Enrique Aguilar-Méndez , Abdiel Espinosa-Champo

Rotational misalignment or twisting of two mono-layers of graphene strongly influences its electronic properties. Structurally, twisting leads to large periodic supercell structures, which in turn can support intriguing strongly correlated…

Twisted bilayers of nodal superconductors were recently proposed as a promising platform to host superconducting phases that spontaneously break time-reversal symmetry. Here we extend this analysis to twisted multilayers, focusing on two…

Superconductivity · Physics 2022-07-28 Tarun Tummuru , Étienne Lantagne-Hurtubise , Marcel Franz

Twisted bilayered graphenes at magic angles are systems housing long ranged periodicity of Moir\'e pattern together with short ranged periodicity associated with the individual graphenes. Such materials are a fertile ground for novel states…

Mesoscale and Nanoscale Physics · Physics 2022-10-11 Pablo Rodriguez-Lopez , Dai-Nam Le , María J. Calderón , Elena Bascones , Lilia M. Woods

Owing to the interaction between the layers, the twisted bilayer two-dimensional materials exhibit numerous unique optical and electronic properties different from the monolayer counterpart, and have attracted tremendous interests in…

Mesoscale and Nanoscale Physics · Physics 2021-08-18 Yabin Ma , Tao Ouyang , Yuanping Chen , Yuee Xie

Twisted bilayer graphene develop quasi-flat bands at specific "magic" interlayer rotation angles through an unconventional mechanism connected to carrier chirality. Quasi-flat bands are responsible for a wealth of exotic,…

Mesoscale and Nanoscale Physics · Physics 2020-11-25 María Rosendo , Fernando Peñaranda , Johan Christensen , Pablo San-Jose

Flatbands with extremely narrow bandwidths on the order of a few mili-electron volts can appear in twisted multilayer graphene systems for appropriate system parameters. Here we investigate the electronic structure of a twisted bi-bilayer…

Mesoscale and Nanoscale Physics · Physics 2019-06-24 Narasimha Raju Chebrolu , Bheema Lingam Chittari , Jeil Jung