Related papers: Graphene-based perfect optical absorbers harnessin…
We study plasmonic resonances in electrostatically gated graphene nanoribbons on silicon dioxide substrates. Absorption spectra are measured in the mid-far infrared and reveal multiple peaks, with width-dependent resonant frequencies. We…
Optical properties of graphene are explored by using the generalized tight-binding model. The main features of spectral structures, the form, frequency, number and intensity, are greatly enriched by the complex relationship among the…
Recently synthesized two-dimensional graphene-like material referred to as graphenylene is a semiconductor with a narrow direct bandgap that holds great promise for nanoelectronic applications. The significant bandgap increase can be…
Graphene has generated exceptional interest as an optoelectronic material because its high carrier mobility and broadband absorption promise to make extremely fast and broadband electro-optic devices possible. Electro-optic graphene…
We report on experiments of perfect absorption for surface gravity waves impinging a wall structured by a subwavelength resonator. By tuning the geometry of the resonator, a balance is achieved between the radiation damping and the…
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…
We theoretically and experimentally investigate the optical absorption properties of heterostructures composed of graphene films and truncated photonic crystals (PCs) in the visible range. The experimental results show that the absorption…
An analytical method for diffraction of a plane electromagnetic wave at periodically-modulated graphene sheet is presented. Both interface corrugation and periodical change in the optical conductivity are considered. Explicit expressions…
We present an efficient graphene-based photodetector with two Fabri-P\'erot cavities. It is shown that the absorption can reach almost 100% around a given frequency, which is determined by the two-cavity lengths. It is also shown that…
For optical communication, information is converted between optical and electrical signal domains at a high rate. The devices to achieve such a conversion are various types of electro-optical modulators and photodetectors. These two types…
Graphene has been considered as a promising material for opto-electronic devices, because of its tunable and wideband optical properties. In this work, we demonstrate electro-refractive phase modulation in graphene at wavelengths from 1530…
The generalized tight-binding model with exact diagonalization method is developed to calculate the optical properties of monolayer graphene in the presence of composite magnetic fields. The ratio of the uniform magnetic field and the…
We study graphene on a photonic crystal operating in the terahertz (THz) spectral range. We show that the absorption of graphene becomes a modulated function of frequency and can be enhanced by more than three times at specific frequency…
Graphene photonics has emerged as a promising platform for providing desirable optical functionality. However, graphene's monolayer-scale thickness fundamentally restricts the available light matter interaction, posing a critical design…
By learning the optimal policy with a double deep Q-learning network, we design ultra-broadband, biomimetic, perfect absorbers with various materials, based the structure of a moths eye. All absorbers achieve over 90% average absorption…
Coherent perfect absorption (CPA) refers to interferometrically induced complete absorption of incident light by a partial absorber independently of its intrinsic absorption (which may be vanishingly small) or its thickness. CPA is…
We experimentally and analytically report broadband and narrowband perfect absorption in two different acoustic waveguide-resonator geometries by the mechanism of critical coupling. In the first geometry the resonator (a Helmholtz…
Surface plasmon resonance (SPR) has been intensively studied and widely employed for light trapping and absorption enhancement. In the mid-infrared and terahertz (THz) regime, graphene supports the tunable SPR via manipulating its Fermi…
We report on the response of graphene to high intensity mid-IR radiation and show that graphene exhibits saturable absorption and significant two-photon absorption in the spectral region from 1.55 $\mu$m to 3.50 $\mu$m (0.35 eV to 0.80 eV).…
A thin conducting sheet - graphene, for example - transmits, absorbs, and reflects radiation. A sheet that is very thin, even vanishingly so, can still produce 50% absorption at normal incidence if it has conductivity corresponding to half…