We study the effect of twist on the electronic structure of H-terminated armchair graphene nanoribbons, for both relaxed and unrelaxed unit cell size. We investigate the band gap change as a function of the twist angle for different ribbon widths. In the case of unrelaxed unit cell size, the band gap closes for smaller twist angles as opposed to relaxed unit cell size. We calculate strain energ...

Interest in graphene since its isolation in 2004 has rapidly escalated. It has been described as nature's thinnest elastic material and its exceptional mechanical and electronic properties make it an extremely exciting material. Within the realm of electronics , it is its one atoms thickness, planar geometry, high current-carrying capacity and thermal conductivity and potential to open a gap wh...

Ashkan Behnam, Feng Xiong, Andrea Cappelli, Ning C. Wang, Enrique A. Carrion, Sungduk Hong, Yuan Dai, Austin S. Lyons, Edmond K. Chow, Enrico Piccinini, Carlo Jacoboni, and Eric Pop Department of Electrical and Computer Engineering and Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA Department of Electrical Engineering, Stanford University, ...

Graphene subject to a spatially uniform, circularly polarized electric field supports a Floquet spectrum with properties akin to those of a topological insulator. The transport properties of this system, however, are complicated by the nonequilibrium occupations of the Floquet states. We address this by considering transport in a two-terminal ribbon geometry for which the leads have well-define...

Metamaterial-based perfect absorbers promise many applications. Perfect absorption is characterized by the complete suppression of transmission and reflection and complete dissipation of the incident energy by the absorptive meta-atoms. A certain absorption spectrum is usually assigned to a bulk medium and serves as a signature of the respective material. Here we show how to use graphene flakes...

Void-defect is a possible origin of ferromagnetic-like feature pure carbon material. Applying density functional theory to void-defect induced graphene-nano-ribbon (GNR), detailed relationship between multiple-spin-state and structure change was studied. An equilateral triangle an initial void having six electrons distorted isosceles by re-bonding atoms. Among spin-states Sz=0/2, 2/2, 4/2 6/2, ...

We present an atomic-resolution observation and analysis of graphene constrictions and ribbons with sub-nanometer width. Graphene membranes are studied by imaging side spherical aberration-corrected transmission electron microscopy at 80 kV. Holes are formed in the honeycomb-like structure due to radiation damage. As the holes grow and two holes approach each other, the hexagonal structure that...