English
Related papers

Related papers: Optical cages made of graphitic frameworks

200 papers

Graphene, owing to its zero bandgap electronic structure, is promising as an absorption material for ultra-wideband photodetection applications. However, graphene-absorption based detectors inherently suffer from poor responsivity due to…

Applied Physics · Physics 2019-08-20 Krishna Murali , Nithin Abraham , Sarthak Das , Sangeeth Kallatt , Kausik Majumdar

Understanding radiation-induced defect formation in carbon materials is crucial for nuclear technology and for the manufacturing of nanostructures with desired properties. Using first principles molecular dynamics, we perform a systematic…

Materials Science · Physics 2007-05-23 Oleg V. Yazyev , Ivano Tavernelli , Ursula Rothlisberger , Lothar Helm

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…

Mesoscale and Nanoscale Physics · Physics 2012-03-29 A. Ferreira , N. M. R. Peres , R. M. Ribeiro , T. Stauber

There has been recent interest in the development of optical analogues of lumped element circuitry, where optical elements act as effective optical inductors, capacitors, and resistors. Such optical circuitry requires the photonic…

The enhanced nonlinear optical response of a one-dimensional (1D) photonic crystal (PC) made from polymers and graphene composites is observed. The graphene PC was fabricated by spin-coating. It shows obvious bandgaps at two wavelengths in…

We numerically and experimentally investigate graphene-based optical absorbers that exploit guided mode resonances (GMRs) achieving perfect absorption over a bandwidth of few nanometers (over the visible and near-infrared ranges) with a…

We describe strategies to estimate the upper limits of the efficiency of photon energy harvesting via hot electron extraction from gapless absorbers. Gapless materials such as noble metals can be used for harvesting the whole solar…

Materials Science · Physics 2018-02-27 Svetlana V. Boriskina , Jiawei Zhou , Zhiwei Ding , Gang Chen

We present a design study of quantum light sources based on hybrid circular Bragg Gratings (CBGs) for emission wavelengths in the telecom O-band. The evaluated CBG designs show photon extraction efficiencies > 95% and Purcell factors close…

Applied Physics · Physics 2019-12-06 Lucas Rickert , Timm Kupko , Sven Rodt , Stephan Reitzenstein , Tobias Heindel

We have used calculations based on density functional theory to investigate the energetics of hydrogen absorption in calcium-intercalated graphites. We focus particularly on the absorption energy and the stability of the hydrogenated…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Charles R. Wood , Neal T. Skipper , Michael J. Gillan

A single-crystal sheet of graphene is synthesized on the low-symmetry substrate Ir(110) by thermal decomposition of C$_2$H$_4$ at 1500 K. Using scanning tunneling microscopy, low-energy electron diffraction, angle-resolved photoemission…

Ultracold atomic gases with uniform density can be created by flat-bottom optical traps. These gases provide an ideal platform to study many-body physics in a system that allows for simple connections with theoretical models and emulation…

This article presents a novel approach for designing dual-band absorbers based on graphene and metallic metasurfaces for terahertz and mid-infrared regimes, respectively. The absorbers are composed of a two-dimensional (2D) array of square…

Optics · Physics 2019-03-27 Saeedeh Barzegar-Parizi , Amin Khavasi

Based on far-infrared spectroscopy of a small sample of nearby infrared-bright and ultraluminous infrared galaxies (ULIRGs) with the ISO Long Wavelength Spectrometer, we find a dramatic progression in ionic/atomic fine-structure emission…

Transport experiments provide conflicting evidence on the possible existence of fractional order within integer quantum Hall systems. In fact integer edge states sometimes behave as monolithic objects with no inner structure, while other…

Mesoscale and Nanoscale Physics · Physics 2012-10-24 Nicola Paradiso , Stefan Heun , Stefano Roddaro , Lucia Sorba , Fabio Beltram , Giorgio Biasiol , L. N. Pfeiffer , K. W. West

Photonic crystal slabs have been widely used in nanophotonics for light confinement, dispersion engineering, nonlinearity enhancement, and other unusual effects arising from their structural periodicity. Sub-micron device sizes and mode…

Optics · Physics 2019-03-08 Ian A. D. Williamson , S. Hossein Mousavi , Zheng Wang

The optical conductance of monolayer graphene is defined solely by the fine structure constant. The absorbance has been predicted to be independent of frequency. In principle, the interband optical absorption in zero-gap graphene could be…

The absorption to mass ratio of the infrared arrays is enhanced to approximately 1.33 to 7.33 times larger than the previously reported structures by incorporating two design characteristics: first, the coupling of evanescent fields in the…

Optics · Physics 2021-02-03 Avijit Das , Joseph J. Talghader

Experimental data on carbon nanotube carpet and synthetic opals have been compared by visible, infrared spectroscopy, and electron microscopy. Spectral features of the objects under study in infrared region are registered. Three regions of…

Optics · Physics 2018-01-01 G. Dovbeshko , O. Fesenko , V. Moiseyenko , V. Gorelik , V. Boyko , V. Sobolev

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…

Materials Science · Physics 2009-11-13 Kin Fai Mak , Matthew Y. Sfeir , Yang Wu , Chun Hung Lui , James A. Misewich , Tony F. Heinz

A photonic integrated circuit comprised of an 11 cm multimode speckle waveguide, a 1x32 splitter, and a linear grating coupler array is fabricated and utilized to receive 2 GHz of RF signal bandwidth from 2.5 to 4.5 GHz using a 35 MHz mode…