Related papers: Moir\'{e} phonons in the twisted bilayer graphene
Minimally twisted bilayer graphene in the presence of an interlayer bias develops a triangular network of valley chiral modes that propagate along the $AB/BA$ interfaces and scatter at the $AA$ regions. The low energy physics of the…
The in-plane optical phonons around 200 meV in few-layer graphene are investigated utilizing infrared absorption spectroscopy. The phonon spectra exhibit unusual asymmetric features characteristic of Fano resonances, which depend critically…
We propose a harmonic linear response (HLR) method to calculate the phonon dispersion relations of two-dimensional (2D) layers from equilibrium simulations at finite temperature. This HLR approach is based on the linear response of the…
Twist angle engineering in van der Waals homo and hetero-bilayers introduces profound modifications in their electronic, optical and mechanical properties due to lattice reconstruction. In these systems, the interlayer coupling and atomic…
A density-matrix formalism within the length gauge is developed for the purpose of calculating the nonlinear response of intrinsic bilayer graphene at terahertz frequencies. Employing a tight-binding model, we find that interplay between…
We calculate the collective charge density excitation dispersion and spectral weight in bilayer semiconductor structures {\it including effects of interlayer tunneling}. The out-of-phase plasmon mode (the ``acoustic'' plasmon) develops a…
We investigate the mesoscopic transport through a twisted bilayer graphene (TBG) consisting of a clean graphene nanoribbon on the bottom and a disordered graphene disc on the top. We show that, with strong top-layer disorder the…
Plasmon and coupled plasmon-phonon modes in graphene are investigated the-oretically within the diagrammatic self-consistent field theory. It shows that two plasmon modes and four coupled plasmon-phonon modes can be excited via intra-and…
We investigate the effect of electron- $\mathrm{A}_{1g}$ phonon coupling on the gapless electronic band dispersion of the pristine graphene. The electron-phonon interaction is introduced through a Kekul\'{e}-type distortion giving rise to…
Recent experiments on multilayer graphene materials have discovered a plethora of correlated phases, including ferromagnetism and superconductivity, in the absence of a moir\'{e} potential. These findings pose an intriguing question of…
In this paper, we propose an extended plane wave framework to make the electronic structure calculations of the twisted bilayer 2D material systems practically feasible. Based on the foundation in [Y. Zhou, H. Chen, A. Zhou, J. Comput.…
It is proved that the acoustic-type dispersion of bending mode in graphene is generated by the fluctuation interaction between in-plane and out-of-plane terms in the free energy arising with account of non-linear components in the graphene…
In twisted bilayers of semiconducting transition metal dichalcogenides (TMDs), a combination of structural rippling and electronic coupling gives rise to periodic moir\'e potentials that can confine charged and neutral excitations. Here, we…
We study analytically the plasmonic modes in the graphene-coated dielectric nanowire, based on the explicit form of nonlinear surface conductivity of graphene. The propagation constants of different plasmonic modes can be tuned by the input…
We present a phenomenological force-constant model developed for the description of lattice dynamics of sp2 hybridized carbon networks. Within this model approach, we introduce a new set of parameters to calculate the phonon dispersion of…
Phonon self-energy corrections have mostly been studied theoretically and experimentally for phonon modes with zone-center (q = 0) wave-vectors. Here, gate-modulated Raman scattering is used to study phonons of a single layer of graphene…
We theoretically investigate the electronic structures of moir\'{e} superlattices arising in monolayer / bilayer graphene stacked on hexagonal boron nitride (hBN) in presence and absence of magnetic field. We develop an effective continuum…
The interlayer energy of the twisting bilayer graphene is investigated by the molecular mechanics method using both the registry-dependent potential and the Lennard-Jones potential. Both potentials show that the interlayer energy is…
Trilayer graphene in both ABA (Bernal) and ABC (rhombohedral) stacking sequences is shown to exhibit intense infrared absorption from in-plane optical phonons. The feature, lying at ~1580 cm-1, changes strongly with electrostatic gating.…
We devise a theory of adsorption of low-energy atoms on suspended graphene membranes maintained at 10 K based on a model of atom-acoustic phonon interactions. Our primary technique includes a non-perturbative method which treats the…