English
Related papers

Related papers: Dynamic Kohn anomaly in twisted bilayer graphene

200 papers

Electron-phonon coupling in magic-angle twisted bilayer graphene is an important but difficult topic. We propose a scheme to simplify and understand this problem. Weighted by the coupling strength with the low-energy heavy electrons ($f$…

Mesoscale and Nanoscale Physics · Physics 2025-04-17 Hao Shi , Wangqian Miao , Xi Dai

When twisted to angles near 1{\deg}, graphene multilayers provide a new window on electron correlation physics by hosting gate-tuneable strongly-correlated states, including insulators, superconductors, and unusual magnets. Here we report…

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

The recent discovery of correlated insulator states and superconductivity in magic-angle twisted bilayer graphene has paved the way to the experimental investigation of electronic correlations in tunable flat band systems realized in…

The family of moir\'e materials provides a powerful platform for tuning interlayer couplings via the twist angle in systems with large spatial periodicity. In trilayer graphene systems, interlayer couplings at the two interfaces can…

Mesoscale and Nanoscale Physics · Physics 2025-04-09 Wei-En Tseng , Mei-Yin Chou

Graphene, a one-layer honeycomb lattice of carbon atoms, exhibits unconventional phenomena and attracts much interest since its discovery. Recently, an unexpected Mott-like insulator state induced by moir\'e pattern and a superconducting…

Mesoscale and Nanoscale Physics · Physics 2019-11-22 Yao Wang , Yi-Jun Chang , Jun Gao , Yong-Heng Lu , Zhi-Qiang Jiao , Fang-Wei Ye , Xian-Min Jin

We report phonon renormalisation in bilayer graphene as a function of doping. The Raman G peak stiffens and sharpens for both electron and hole doping, as a result of the non-adiabatic Kohn anomaly at the $\Gamma$ point. The bilayer has two…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 A. Das , B. Chakraborty , S. Piscanec , S. Pisana , A. K. Sood , A. C. Ferrari

Phonon dispersions generically display non-analytic points, known as Kohn anomalies, due to electron-phonon interactions. We analyze this phenomenon for a zone boundary phonon in undoped graphene. When electron-electron interactions with…

Strongly Correlated Electrons · Physics 2012-03-22 Fernando de Juan , Herbert A. Fertig

We report planar tunneling spectroscopy measurements on metal-WSe$_2$-twisted bilayer graphene heterostructures across a broad range of gate and bias voltages. The observed experimental features are attributed to phonon-assisted tunneling…

Tailoring the interlayer twist angle of bilayer graphene (BLG) has a significant influence on its electronic properties, including superconductivity, topological transitions, ferromagnetic states and correlated insulating states. These…

The ability to control the strength of interaction is essential for studying quantum phenomena emerging from a system of correlated fermions. For example, the isotope effect illustrates the effect of electron-phonon coupling on…

Mesoscale and Nanoscale Physics · Physics 2021-03-31 Xiaoxue Liu , Zhi Wang , K. Watanabe , T. Taniguchi , Oskar Vafek , J. I. A. Li

Twisted bilayer graphene (tBLG) forms a quasicrystal whose structural and electronic properties depend on the angle of rotation between its layers. Here we present a scanning tunneling microscopy study of gate-tunable tBLG devices supported…

We investigate bilayers of nanoporous graphene (NPG), laterally bonded carbon nanoribbons, and graphene. The electronic and transport properties are explored as a function of the interlayer twist angle using an atomistic tight-binding model…

Mesoscale and Nanoscale Physics · Physics 2024-08-12 Xabier Diaz de Cerio , Aleksander Bach Lorentzen , Mads Brandbyge , Aran Garcia-Lekue

Two-dimensional (2D) materials have attracted significant interest due to their tunable physical properties when stacked into homo- and hetero-structures. Twisting adjacent layers introduces moir\'{e} patterns that strongly influence the…

Recent scanning tunneling microscopy experiments [K.P. Nuckolls et al., arXiv:2303.00024] have revealed the ubiquity of Kekul\'e charge-density wave order in magic-angle twisted bilayer graphene. Most samples are moderately strained and…

Strongly Correlated Electrons · Physics 2025-02-06 Yves H. Kwan , Glenn Wagner , Nick Bultinck , Steven H. Simon , Erez Berg , S. A. Parameswaran

We report a local minimum in thermal conductivity in twisted bilayer graphene (TBG) at the angle of 1.08$^\circ$, which corresponds to the 'magic angle' in the transition of several other reported properties. Within the supercell of a…

Mesoscale and Nanoscale Physics · Physics 2024-09-12 Yajuan Cheng , Zheyong Fan , Tao Zhang , Masahiro Nomura , Sebastian Volz , Guimei Zhu , Baowen Li , Shiyun Xiong

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

Electron collimation via a graphene pn-junction allows electrostatic control of ballistic electron trajectories akin to that of an optical circuit. Similar manipulation of novel correlated electronic phases in twisted-bilayer graphene…

Mesoscale and Nanoscale Physics · Physics 2024-04-02 Wei Ren , Xi Zhang , Ziyan Zhu , Moosa Khan , Kenji Watanabe , Takashi Taniguchi , Efthimios Kaxiras , Mitchell Luskin , Ke Wang

The introduction of 'twist' or relative rotation between two atomically thin van der Waals (vdW) membranes gives rise to periodic Moire potential, leading to a substantial altercation of the band structure of the planar assembly. While most…

Mesoscale and Nanoscale Physics · Physics 2020-12-30 Phanibhusan S Mahapatra , Bhaskar Ghawri , Kenji Watanabe , Takashi Taniguchi , Subroto Mukerjee , Arindam Ghosh

Twisted bilayer graphene (tBLG) including interlayer interaction and rotational disorder shows anomalous electron transport as a function of twist-angles (tAs). In this work, we address the electronic properties and electron transport of…

Mesoscale and Nanoscale Physics · Physics 2023-06-13 Farzaneh Shayeganfar , Ali Ramazani , Nicholas X Fang
‹ Prev 1 3 4 5 6 7 10 Next ›