Related papers: High optical absorption in graphene
The electronic and optical properties of mono, di, tri, and tetravacancies in graphene are studied in comparison to each other, using density functional theory. In addition, oxidized monovacancies are considered for different oxygen…
This review on graphene, a one atom thick, two-dimensional sheet of carbon atoms, starts with a general description of the graphene electronic structure as well as a basic experimental toolkit for identifying and handling this material.…
In this paper, a photonic crystal containing graphene and metamaterial layers is investigated. The absorption spectrum of the structure in the terahertz range is obtained using the transfer matrix method. The results show that by adding a…
We investigate the effect of hydrogen coverage on the optical conductivity of single-side hydrogenated graphene from first principles calculations. To account for different degrees of uniform hydrogen coverage we calculate the complex…
Here, we report on controlling strain in graphene by trapping molecules at the graphene-substrate interface, leveraging molecular dipole moments. Spectroscopic and transport measurements show that strain correlates with the dipole moments…
We show that the optical transparency of suspended graphene is defined by the fine structure constant, alpha, the parameter that describes coupling between light and relativistic electrons and is traditionally associated with quantum…
Optical reflectivity and transmission measurements over photon energies between 0.2 and 1.2 eV were performed on single-crystal graphene samples on a transparent SiO2 substrate. For photon energies above 0.5 eV, graphene yielded a…
We investigate 1D aperiodic multilayer microstructures in order to achieve near total absorption in preselected wavelengths in a graphene monolayer. Our structures are designed by a genetic optimization algorithm coupled to a transfer…
We demonstrate that optical transparency of any two-dimensional system with a symmetric electronic spectrum is governed by the fine structure constant and suggest a simple formula that relates a quasi-particle spectrum to an optical…
Graphene has shown great potentials for high-speed photodetection. Yet, the responsivities of graphene-based high-speed photodetectors are commonly limited by the weak effective absorption of atomically thin graphene. Here, we propose and…
The ultrafast response and broadband absorption of all-optical graphene switches are highly desirable features for on-chip photonic switching. However, because graphene is an atomically thin material, its absorption of guided optical modes…
We measure the adsorption height of hydrogen-intercalated quasi-free-standing monolayer graphene on the (0001) face of 6H silicon carbide by the normal incidence x-ray standing wave technique. A density functional calculation for the full…
Graphene is ideally suited for optoelectronic applications. It offers absorption at telecom wavelengths, high-frequency operation and CMOS-compatibility. We report optoelectronic mixing up to to 67GHz using a back-gated graphene field…
We show that for graphene with any finite difference in the on-site energy between the two sub-lattices ($\Delta$), The optical absorption edge is determined by the $\Delta$. The universal conductance will be broken and the conductance near…
A model for the rival mechanisms of hysteresis in graphene channel resistivity on a substrate of different nature dependence on a gate voltage - a direct one (caused by adsorbates with dipole moment on surface and interface) and an inverse…
Motivated by the recent realization of graphene sensors to detect individual gas molecules, we investigate the adsorption of H2O, NH3, CO, NO2, and NO on a graphene substrate using first-principles calculations. The optimal adsorption…
Graphene is a 2-dimensional material with high carrier mobility and thermal conductivity, suitable for high-speed electronics. Conduction and valence bands touch at the Dirac point. The absorptivity of single-layer graphene is 2.3%, nearly…
We theoretically study the transmittance for normal incidence of linearly polarized light between two media separated by a strained graphene monolayer. We analytically characterize the degree of dichroism and the transparency of graphene as…
We study optical absorption at graphene edges in a transversal magnetic field. The magnetic field bends the trajectories of particle- and hole excitations into antipodal direction which generates a directed current. We find a rather strong…
The analytic expressions for the maximum and minimum reflectance of optical films coated with gapped graphene are derived in the application region of the Dirac model with account of multiple reflections. The respective film thicknesses are…