中文
相关论文

相关论文: Exceptional magic angles in non-Hermitian twisted …

200 篇论文

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…

Twisted trilayer graphene (TLG) may be the simplest realistic system so far, which has flat bands with nontrivial topology. Here, we give a detailed calculation about its band structures and the band topology, i.e. valley Chern number of…

介观与纳米尺度物理 · 物理学 2021-03-31 Zhen Ma , Shuai Li , Ya-Wen Zheng , Meng-Meng Xiao , Hua Jiang , Jin-Hua Gao , X. C. Xie

We study the anomalous Hall effect, magneto-optical properties, and nonlinear optical properties of twisted bilayer graphene (TBG) aligned with hexagonal boron nitride (hBN) substrate as well as twisted double bilayer graphene systems. We…

介观与纳米尺度物理 · 物理学 2021-01-27 Jianpeng Liu , Xi Dai

A purely electronic mechanism is proposed for the unconventional superconductivity recently observed in twisted bilayer graphene (tBG) close to the magic angle. Using the Migdal-Eliashberg framework on a one parameter effective lattice…

介观与纳米尺度物理 · 物理学 2024-02-19 Gargee Sharma , Maxim Trushin , Oleg P. Sushkov , Giovanni Vignale , Shaffique Adam

We investigate the band structure of twisted monolayer-bilayer graphene (tMBG), or twisted graphene on bilayer graphene (tGBG), as a function of twist angles and perpendicular electric fields in search of optimum conditions for achieving…

介观与纳米尺度物理 · 物理学 2020-07-15 Youngju Park , Bheema Lingam Chittari , Jeil Jung

Twisting bilayer sheets of graphene have been proven to be an efficient way to manipulate the electronic Dirac-like properties, resulting in flat bands at magic angles. Inspired by the electronic model, we develop a continuum model for the…

Recent experimental and theoretical investigations demonstrate that twisted trilayer graphene (tTLG) is a highly tunable platform to study the correlated insulating states, ferromagnetism, and superconducting properties. Here we explore the…

介观与纳米尺度物理 · 物理学 2021-11-17 Zewen Wu , Xueheng Kuang , Zhen Zhan , Shengjun Yuan

Moir\'e superlattices in two-dimensional (2D) van der Waals (vdW) heterostructures provide 20 an efficient way to engineer electron band properties. The recent discovery of exotic quantum phases and their interplay in twisted bilayer…

Recent experiments on magic-angle twisted bilayer graphene have discovered correlated insulating behavior and superconductivity at a fractional filling of an isolated narrow band. In this paper we show that magic-angle bilayer graphene…

A number of moir\'e graphene systems have nearly flat topological bands where electron motion is strongly correlated. Though microscopically these systems are only quasiperiodic, they can typically be treated as translation invariant to an…

介观与纳米尺度物理 · 物理学 2021-03-10 Dan Mao , T. Senthil

In twisted bilayer graphene (TBG) a moir\'e pattern forms that introduces a new length scale to the material. At the 'magic' twist angle of 1.1{\deg}, this causes a flat band to form, yielding emergent properties such as correlated…

Two monolayers of graphene twisted by a small `magic' angle exhibit nearly flat bands leading to correlated electronic states and superconductivity, whose precise nature including possible broken symmetries, remain under debate. Here we…

强关联电子 · 物理学 2019-12-13 Jong Yeon Lee , Eslam Khalaf , Shang Liu , Xiaomeng Liu , Zeyu Hao , Philip Kim , Ashvin Vishwanath

The understanding of strongly-correlated materials, and in particular unconventional superconductors, has puzzled physicists for decades. Such difficulties have stimulated new research paradigms, such as ultra-cold atom lattices for…

介观与纳米尺度物理 · 物理学 2018-05-22 Yuan Cao , Valla Fatemi , Shiang Fang , Kenji Watanabe , Takashi Taniguchi , Efthimios Kaxiras , Pablo Jarillo-Herrero

We combine state-of-the-art large-scale first principles calculations with a low-energy continuum model to describe the nearly flat bands of twisted bilayer graphene at the first magic angle $\theta =1.08^\circ$. We show that the energy…

介观与纳米尺度物理 · 物理学 2019-05-22 Procolo Lucignano , Dario Alfè , Vittorio Cataudella , Domenico Ninno , Giovanni Cantele

We introduce a minimum tight-binding model with only three parameters extracted from graphene and untwisted bilayer graphene. This model reproduces quantitatively the electronic structure of not only these two systems and bulk graphite near…

介观与纳米尺度物理 · 物理学 2018-09-12 Xianqing Lin , David Tománek

Superlattices from twisted graphene mono- and bi-layer systems give rise to on-demand many-body states such as Mott insulators and unconventional superconductors. These phenomena are ascribed to a combination of flat bands and strong…

Twisted bilayer graphene has been argued theoretically to host exceptionally flat bands when the angle between the two layers falls within a magic range near 1.1$^\circ$. This is now strongly supported by experiment, which furthermore…

强关联电子 · 物理学 2019-07-24 Kasra Hejazi , Chunxiao Liu , Leon Balents

The nature of correlated states in twisted bilayer graphene (TBG) at the magic angle has received intense attention in recent years. We present a numerical study of an interacting Bistritzer-MacDonald (IBM) model of TBG using a suite of…

We present a theoretical study of the intrinsic plasmonic properties of twisted bilayer graphene (TBG) as a function of the twist angle $\theta$ (and other microscopic parameters such as temperature and filling factor). Our calculations,…

介观与纳米尺度物理 · 物理学 2024-09-06 Lorenzo Cavicchi , Iacopo Torre , Pablo Jarillo-Herrero , Frank H. L. Koppens , Marco Polini

We study the electron-phonon coupling in twisted bilayer graphene (TBG), which was recently experimentally observed to exhibit superconductivity around the magic twist angle $\theta\approx 1.05^\circ$. We show that phonon-mediated electron…

介观与纳米尺度物理 · 物理学 2019-07-03 Biao Lian , Zhijun Wang , B. Andrei Bernevig