English
Related papers

Related papers: Tunable band gap in twisted bilayer graphene

200 papers

We present a theoretical study of the local optical conductivity, plasmon spectra, and thermoelectric properties of twisted bilayer graphene (TBG) at different filling factors and twist angles $\theta$. Our calculations are based on the…

Mesoscale and Nanoscale Physics · Physics 2020-09-04 Pietro Novelli , Iacopo Torre , Frank H. L. Koppens , Fabio Taddei , Marco Polini

Controlling the electronic structure of two-dimensional materials using the combination of twist angle and electrostatic doping is an effective means to induce emergent phenomena. In bilayer graphene with an interlayer twist angle near the…

Control over minivalley polarization and interlayer coupling is demonstrated in double bilayer graphene twisted with an angle of 2.37$^\circ$. This intermediate angle is small enough for the minibands to form and large enough such that the…

Inter-twisted bilayers of two-dimensional (2D) materials can host low-energy flat bands, which offer opportunity to investigate many intriguing physics associated with strong electron correlations. In the existing systems, ultra-flat bands…

Computational Physics · Physics 2022-03-01 Shengdan Tao , Xuanlin Zhang , Jiaojiao Zhu , Pimo He , Shengyuan A. Yang , Yunhao Lu , Su-Huai Wei

We propose a tunable optical setup to engineer topologically nontrivial flat bands in twisted bilayer graphene under circularly polarized light. Using both analytical and numerical calculations, we demonstrate that nearly flat bands can be…

Strongly Correlated Electrons · Physics 2020-12-18 Yantao Li , H. A. Fertig , Babak Seradjeh

Over the years, great efforts have been devoted in introducing a sizable and tunable band gap in graphene for its potential application in next-generation electronic devices. The primary challenge in modulating this gap has been the absence…

We report on a double moir\'e system consisting of four graphene layers, where the top and bottom pairs form small-twist-angle bilayer graphene, and the middle interface has a large rotational mismatch. This system shows clear signatures of…

We consider the stability of fragile topological bands protected by space-time inversion symmetry in the presence of strong electron-electron interactions. At the single-particle level, the topological nature of the bands prevents the…

Strongly Correlated Electrons · Physics 2022-02-21 Ari M. Turner , Erez Berg , Ady Stern

Incommensurately twisted graphene bilayers are described by long-wavelength theories, but to date such theories exist only at small angles of interlayer rotation. We construct a long wavelength theory without such a restriction, instead…

Mesoscale and Nanoscale Physics · Physics 2014-09-09 Hridis K. Pal , Steven Carter , M. Kindermann

The interplay between interlayer van der Waals interaction and intralayer lattice distortion can lead to structural reconstruction in slightly twisted bilayer graphene (TBG) with the twist angle being smaller than a characteristic angle…

Mesoscale and Nanoscale Physics · Physics 2020-07-07 Yi-Wen Liu , Ying Su , Xiao-Feng Zhou , Long-Jing Yin , Chao Yan , Si-Yu Li , Wei Yan , Sheng Han , Zhong-Qiu Fu , Yu Zhang , Qian Yang , Ya-Ning Ren , Lin He

We investigate the bandwidth compression due to out of plane pressure of the moire flatbands near charge neutrality in twisted bilayer graphene for a continuous range of small rotation angles of up to $\sim2.5^{\circ}$. The flatband…

Mesoscale and Nanoscale Physics · Physics 2019-01-29 Bheema Lingam Chittari , Nicolas Leconte , Srivani Javvaji , Jeil Jung

Twisted bilayer graphene with a twist angle of around 1.1{\deg} features a pair of isolated flat electronic bands and forms a strongly correlated electronic platform. Here, we use scanning tunneling microscopy to probe local properties of…

This is a theoretical study of electron transport in gated bilayer graphene - a novel semiconducting material with a tunable band gap. It is shown that the which-layer pseudospin coherence enhances the subgap conductivity and facilitates…

Mesoscale and Nanoscale Physics · Physics 2012-05-28 Maxim Trushin

When using hexagonal boron-nitride (hBN) as a substrate for graphene, the resulting moir\'e pattern creates secondary Dirac points. By encapsulating a multilayer graphene within aligned hBN sheets the controlled moir\'e stacking may offer…

Mesoscale and Nanoscale Physics · Physics 2023-02-14 Robin Smeyers , Lucian Covaci , Milorad V. Milošević

We develop a theory for a qualitatively new type of disorder in condensed matter systems arising from local twist-angle fluctuations in two strongly coupled van der Waals monolayers twisted with respect to each other to create a flat band…

Disordered Systems and Neural Networks · Physics 2020-06-30 Justin H. Wilson , Yixing Fu , S. Das Sarma , J. H. Pixley

The bands of graphite are extremely sensitive to topological defects which modify the electronic structure. In this paper we found non-dispersive flat bands no farther than 10 meV of the Fermi energy in slightly twisted bilayer graphene as…

Mesoscale and Nanoscale Physics · Physics 2010-12-21 E. Suárez Morell , J. D. Correa , P. Vargas , M. Pacheco , Z. Barticevic

Twisted bilayer graphene (TBG) exhibits a wide range of intriguing physical properties, such as superconductivity, ferromagnetism, and superlubricity. Depending on the twist angle, periodic moir\'e superlattices form in twisted bilayer…

Mesoscale and Nanoscale Physics · Physics 2022-06-07 Vahid Morovati , Zhiming Xue , Kenneth M. Liechti , Rui Huang

For graphene to be utilized in the digital electronics industry the challenge is to create bandgaps of order 1eV as simply as possible. The most successful methods for the creation of gaps in graphene are (a) confining the electrons in…

Mesoscale and Nanoscale Physics · Physics 2014-03-13 A. R. Davenport , J. P. Hague

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…

Mesoscale and Nanoscale Physics · Physics 2020-07-15 Youngju Park , Bheema Lingam Chittari , Jeil Jung

Moir\'e superlattices created by the twisted stacking of two-dimensional crystalline monolayers can host electronic bands with flat energy dispersion in which interaction among electrons is strongly enhanced. These superlattices can also…

Mesoscale and Nanoscale Physics · Physics 2021-05-18 Xiaomeng Liu , Cheng-Li Chiu , Jong Yeon Lee , Gelareh Farahi , Kenji Watanabe , Takashi Taniguchi , Ashvin Vishwanath , Ali Yazdani