Related papers: Directional photoelectric current across the bilay…
Conventional field effect transistor operation in graphene is limited by its zero gap and minimum quantum conductivity. In this work, we report on controlled electrochemical modification of graphene such that its conductance changes by more…
Chiral light matter interaction enables new fundamental researches and applications of light. The interaction has traditionally faced challenges in low directionality and efficiency based on spin orbit interaction of light in microscopic…
We theoretically study the effects of electron-electron interaction in twisted bilayer graphene in applied transverse dc electric field. When the twist angle is not very small, the electronic spectrum of the bilayer consists of four Dirac…
The nematic phase transition in electronic liquids, driven by Coulomb interactions, represents a new class of strongly correlated electronic ground states. We studied suspended samples of bilayer graphene, annealed so that it achieves very…
Magic-angle twisted bilayer graphene displays a complex phase diagram as a function of flat band filling, featuring compressibility cascade transitions and a variety of competing ground states with broken spin, valley and point group…
We argue that the presence of a very strong magnetic field in the chirally broken phase induces inhomogeneous expectation values, of a spiral nature along the magnetic field axis, for the currents of charge and chirality, when there is…
Electron transport in bilayer graphene placed under a perpendicular electric field is revealed experimentally. Steep increase of the resistance is observed under high electric field; however, the resistance does not diverge even at low…
We show that negative refraction with minimal absorption can be obtained by means of quantum interference effects similar to electromagnetically induced transparency. Coupling a magnetic dipole transition coherently with an electric dipole…
We consider tunneling transport between two parallel graphene sheets where one is a single-layer sample and the other one a bilayer. In the presence of an in-plane magnetic field, the interplay between combined energy and momentum…
We analyze the response of bilayer graphene to an external transverse electric field using a variational method. A previous attempt to do so in a recent paper by Falkovsky [Phys. Rev. B 80, 113413 (2009)] is shown to be flawed. Our…
Negative differential conductance and tunneling characteristics of two-terminal graphene devices are observed before and after electric breakdown, respectively. The former is caused by the strong scattering under a high E-field, and the…
A new class of photocurrents is predicted to occur in both type-I and type-II Weyl semimetals. Unlike the previously studied photocurrents in chiral materials, the proposed current requires neither circularly polarized light, nor an absence…
The valley degree of freedom in 2D materials can be manipulated for low-dissipation quantum electronics called valleytronics. At the boundary between two regions of bilayer graphene with different atomic or electrostatic configuration,…
A method is derived to solve the massless Dirac-Weyl equation describing electron transport in a mono-layer of graphene with a scalar potential barrier U(x,t), homogeneous in the y-direction, of arbitrary x- and time dependence. Resonant…
Graphene-like materials can be effectively described by Quantum Electrodynamics in (2+1)-dimensions. In a pristine state, these systems exhibit a symmetry between the nonequivalent Dirac points in the honeycomb lattice. Realistic samples…
We theoretically investigate optical injection processes, including one- and two-photon carrier injection and two-color coherent current injection, in twisted bilayer graphene with moderate angles. The electronic states are described by a…
The phenomena of crystal size changes and structural phase transitions induced by light irradiation have garnered significant interest due to their potential for tuning and controlling a wide range of material properties through highly…
Photoconductivity of novel materials is the key property of interest for design of photodetectors, optical modulators, and switches. Despite the photoconductivity of most novel 2d materials has been studied both theoretically and…
Whereas massless Dirac fermions in monolayer graphene exhibit Klein tunneling when passing through a potential barrier upon normal incidence, such a barrier totally reflects massive Dirac fermions in bilayer graphene due to difference in…
We demonstrate a photonic analog of twisted bilayer graphene that has ultra-flat photonic bands and exhibits extreme slow light behavior. Our twisted bilayer photonic device, which has an operating wavelength in C-band of the telecom…