English
Related papers

Related papers: Dynamic polarization and plasmons in kekul\'e-patt…

200 papers

Elastic deformations of graphene can significantly change the flow paths and valley polarization of the electric currents. We investigate these phenomena in graphene nanoribbons with localized out-of-plane deformations by means of…

Mesoscale and Nanoscale Physics · Physics 2019-03-12 Thomas Stegmann , Nikodem Szpak

We introduce a generalized Hamiltonian describing not only all topological phases observed experimentally in Kekul\'e graphene (KekGr) but predicting also new ones. These phases show features like a quadratic band crossing point, valley…

Mesoscale and Nanoscale Physics · Physics 2021-11-12 Santiago Galván y García , Thomas Stegmann , Yonatan Betancur-Ocampo

The electron transport of different conical valleys is investigated in graphene with extended line-defects. Intriguingly, the electron with a definite incident angle can be completely modulated into one conical valley by a resonator which…

Mesoscale and Nanoscale Physics · Physics 2013-12-02 Yang Liu , Juntao Song , Yuxian Li , Ying Liu , Qing-feng Sun

The joint effects of Kekul\'e lattice distortions and Rashba-type spin-orbit coupling on the electronic properties of graphene are explored. We modeled the position dependence of the Rashba energy term in a manner that allows its seamless…

The transport properties of electrons in graphene $p$-$n$ junction with uniform Kekul\'e lattice distortion have been studied using the tight-binding model and the Landauer-B\"uttiker formalism combined with the nonequilibrium Green's…

Mesoscale and Nanoscale Physics · Physics 2023-07-19 Peipei Zhang , Chao Wang , Yu-Xian Li , Lixue Zhai , Juntao Song

Breaking the intrinsic chirality of quasiparticles in graphene enables the emergence of new and intriguing phases. One such paradigmatic example is the bond density wave, which leads to a Kekul\'{e}-ordered structure and underpins exotic…

Mesoscale and Nanoscale Physics · Physics 2025-06-23 Dominik Szczȩśniak

The interaction between electrons in graphene under high magnetic fields drives the formation of a rich set of quantum Hall ferromagnetic phases (QHFM), with broken spin or valley symmetry. Visualizing atomic scale electronic wavefunctions…

Mesoscale and Nanoscale Physics · Physics 2022-02-02 Xiaomeng Liu , Gelareh Farahi , Cheng-Li Chiu , Zlatko Papic , Kenji Watanabe , Takashi Taniguchi , Michael P. Zaletel , Ali Yazdani

One of the intriguing characteristics of honeycomb lattices is the appearance of a pseudo-magnetic field as a result of mechanical deformation. In the case of graphene, the Landau quantization resulting from this pseudo-magnetic field has…

We show that the optical excitation of graphene with polarized light leads to the pure valley current where carriers in the valleys counterflow. The current in each valley originates from asymmetry of optical transitions and electron…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 L. E. Golub , S. A. Tarasenko , M. V. Entin , L. I. Magarill

Intervalley scattering of carriers in graphene at `top' adatoms may give rise to a hidden Kekul\'e ordering pattern in the adatom positions. This ordering is the result of a rapid modulation in the electron-mediated interaction between…

Mesoscale and Nanoscale Physics · Physics 2018-05-02 L. González-Árraga , F. Guinea , P. San-Jose

We theoretically investigate under which conditions nonlocal plasmon response in monolayer graphene can be detected. To this purpose, we study optical scattering off graphene plasmon resonances coupled using a subwavelength dielectric…

Mesoscale and Nanoscale Physics · Physics 2025-02-19 Tobias Wenger , Giovanni Viola , Philippe Tassin , Mikael Fogelström , Jari Kinaret

Analogous to charge and spin, electrons in solids endows an additional degree of freedom: the valley pseudospin. Two-dimensional hexagonal materials such as graphene exhibit two valleys, labelled as $\mathbf{K}$ and $\mathbf{K}^{\prime}$.…

Mesoscale and Nanoscale Physics · Physics 2022-01-12 M. S. Mrudul , Gopal Dixit

We study the collective charge excitations (plasmons) in spin polarized graphene, and derive explicit expressions for their dispersion in the undamped regime. From this, we are able to calculate the critical wave vector beyond which the…

Mesoscale and Nanoscale Physics · Physics 2015-06-16 Amit Agarwal , Giovanni Vignale

Employing tight-binding model we investigate the effects of a uniform Y-shaped Kekule lattice distortion on the electronic spectrum and optical conductivity of graphene. We derive a low-energy effective Hamiltonian which is found to be in…

Mesoscale and Nanoscale Physics · Physics 2023-01-03 Yawar Mohammadi

The spin and valley polarizations and plasmonics in Van der Waals heterostructures of strained graphene monolayer on 2D transition metal dichalcogenide (GrTMD) substrate are reported in this communication. The substrate induced interactions…

Mesoscale and Nanoscale Physics · Physics 2017-09-05 Partha Goswami

Graphene's optical properties in the infrared and terahertz can be tailored and enhanced by patterning graphene into periodic metamaterials with sub-wavelength feature sizes. Here we demonstrate polarization sensitive and gate tunable…

Mesoscale and Nanoscale Physics · Physics 2013-06-05 Marcus Freitag , Tony Low , Wenjuan Zhu , Hugen Yan , Fengnian Xia , Phaedon Avouris

We propose an all-electrical setup to generate valley polarization in graphene. A finite graphene sheet is connected to two normal metal electrodes each with two terminals along its zigzag edges, while the armchair edges remain free. When a…

Mesoscale and Nanoscale Physics · Physics 2025-06-30 Sachchidanand Das , Abhiram Soori

Active control of the radiative properties of quantum emitters through engineered light-matter interactions is a key challenge in nanophotonics and quantum optics. In this work, we demonstrate dynamic modulation of dipole's decay rate by…

Applied Physics · Physics 2025-10-23 Hira Asif , Taner Tarik Aytas , Ramazan Sahin

In this study we report our numerical results on finite temperature non-interacting dynamical polarization function, plasmon modes and electron energy loss function of doped single layer gapped graphene within the random phase…

Mesoscale and Nanoscale Physics · Physics 2015-04-07 Digish K. Patel , Syed S. Z. Ashraf , Ami C. Sharma

For gapped graphene, we predict that an intense ultrashort (single-oscillation) circularly-polarized optical pulse can induce a large population of the conduction band and a large valley polarization. With an increase in the bandgap, the…

Mesoscale and Nanoscale Physics · Physics 2019-09-25 S. Azar Oliaei Motlagh , Fatemeh Nematollahi , Vadym Apalkov , Mark I. Stockman