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- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 IEEE Research and Applications of Photonics In Defense Conference (RAPID) - Miramar Beach, FL (2018.8.22-2018.8.24)] 2018 IEEE Research and Applications of Photonics In Defense Conference (RAPID) - Implementing Photonic Crystals, Instead of Metamaterials, in the Media of Transformation Optics-based Devices
摘要： Extending Transformation Optics in optical range is challenging because of losses in metamaterials. We propose, instead, to use dielectric photonic crystals capable of supporting superluminal wave propagation and realizing spatial dispersion of refractive index values. Implementing these materials in cylindrical invisibility cloaks is demonstrated.
关键词： spatial dispersion of indices,superluminal wave propagation,anisotropic photonic crystals
更新于2025-09-23 15:19:57
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Effects of higher-order dispersion on photon-pair generation by four-wave mixing
摘要： We present analytical results revealing the impact of higher-order dispersion on four-wave mixing in quantum applications. We derive fundamental relations between input and output modes in dispersive four-wave mixing processes and apply the theory to photon-pair generation. We analyze specific examples of four-wave-mixing configurations and find that, in some cases, spectral correlations are severely affected by dispersion while other cases are strongly unaffected. For the considered examples, we derive analytic conditions for dispersion cancellation, resulting in highly factorable two-photon states.
关键词： spectral correlations,higher-order dispersion,photon-pair generation,quantum applications,four-wave mixing,dispersion cancellation
更新于2025-09-19 17:15:36
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[IEEE 2018 11th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP) - Budapest (2018.7.18-2018.7.20)] 2018 11th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP) - Using Tunable Dispersion-Compensated Modules to Overcome the Power Penalty of a Millimeter-Wave Opto-Electronic Oscillator Signal that is Distributed via a Passive Optical Network for 5G Networks
摘要： The opto-electronic oscillator (OEO), used as a high-frequency oscillator to produce millimeter-wave (mm-W) signals with a low phase noise, is a suitable candidate for fifth-generation (5G) networks in the mm-W range. Since a mm-W OEO is too expensive for every 5G base-station, another option is to employ the OEO at the central-office to feed the base-stations via a passive optical network (PON) infrastructure. The lengths of the PON branches introduce a large power penalty to the transmitted mm-W OEO signal due to the chromatic dispersion of the optical fiber. In this paper the idea of upgrading the PON branches with tunable dispersion-compensated modules to have power-penalty-free transmission is proposed. By overcoming the power-penalty problem in the mm-W range, the integrated optical dispersion-compensated modules are used to minimize the influence of the dispersion in the standard single-mode optical fiber used in the PON.
关键词： power penalty,5G mobile networks,chromatic dispersion,tunable dispersion-compensated module
更新于2025-09-19 17:15:36
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Broadband Dispersion Compensation of Single Mode Fiber by using Modified Decagonal Photonic Crystal Fiber having High Birefringence
摘要： This paper presents a highly birefringent dispersion compensating microstructure modified decagonal photonic crystal fiber for broadband transmission communication system. According to simulation, negative dispersion coefficient of ?610 ps/(nm.km) and a relative dispersion slope (RDS) close to that of single mode fiber of about 0.0036 nm-1 with birefringence of the order 2.1×10-2 was obtained at 1550 nm. The variation of structural parameters is also studied to evaluate the tolerance of the fabrication. Moreover, effective area, residual dispersion, effective dispersion, confinement loss, and nonlinear coefficient of the proposed modified decagonal photonic crystal fiber (M-DPCF) are also mentioned and discussed.
关键词： Photonic crystal fiber,Birefringence,Dispersion compensating fiber,Effective mode area,Residual dispersion,Full-vector Finite Element Method
更新于2025-09-19 17:15:36
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Metamaterials and chiral sensing: a review of fundamentals and applications
摘要： Chirality, a property of broken mirror symmetry, prevails in nature. Chiral molecules show different biochemical behaviors to their mirror molecules. For left or right circularly polarized lights, the fundamental chiral states of electromagnetic fields interact differently with chiral matter, and this effect has been used as a powerful tool for the detection of chiral molecules. This optical sensing, also termed chiral sensing, is not only easy to implement but also non-invasive to the analytes. However, the measurements made by the optical sensing of chiral molecules are challenging, as chiroptical signals are extremely weak. Recent years have seen active research efforts into metamaterial and plasmonic platforms for manipulating local fields to enhance chiroptical signals. This metamaterial approach offers new possibilities of chiral sensing with high sensitivity. Here, we review the recent advances in chiral sensing using metamaterial and plasmonic platforms. In addition, we explain the underlying principles behind the enhancement of chiroptical signals and highlight practically efficient chiral sensing platforms. We also provide perspectives that shed light on design considerations for chiral sensing metamaterials and discuss the possibility of other types of chiral sensing based on resonant metamaterials.
关键词： chiral sensing,chiral molecules,optical rotatory dispersion (ORD),chiroptical spectroscopy,circular dichroism (CD),enantiomers,plasmonics,metamaterials,optical spectroscopy
更新于2025-09-19 17:15:36
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First-principles study of electron dynamics with explicit treatment of momentum dispersion on Si nanowires along different directions
摘要： In this research, ground-state electronic structure and optical properties along with photoinduced electron dynamics of Si nanowires oriented in various directions are reviewed. These nanowires are significant functional units of future nano-electronic devices. All observables are computed for a distribution of wave vectors at ambient temperature. Optical properties are computed under the approximation of momentum conservation. The total absorption is composed of partial contributions from fixed values of momentum. The on-the-fly non-adiabatic couplings obtained along the ab initio molecular dynamics nuclear trajectories are used as parameters for Redfield density matrix equation of motion. The main outcomes of this study are transition energies, light absorption spectra, electron and hole relaxation rates, and electron transport properties. The results of these calculations would contribute to the understanding of the mechanism of electron transfer process on the Si nanowires for optoelectronic applications.
关键词： nanowires,excited state dynamics,nonadiabatic,Momentum dispersion,silicon
更新于2025-09-19 17:15:36
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Absorption-transmission-integrated frequency selective structure based on spoof surface plasmon polariton modes
摘要： A method of engineering the frequency selective structure with absorption and transmission based on spoof surface plasmon polariton (SSPP) modes is proposed and demonstrated in this paper. High-efficiency transmission can be achieved based on SSPP modes coupling. Due to the electric field enhancement effect of the coupled SSPP on the metallic blade array, high-efficiency absorption can be achieved by the high loss of the FR4 dielectric substrate. To verify this method, the absorption-transmission-integrated frequency selective structure was designed using the metallic trapezoid structure, metallic fishbone structure and FSS. The metallic trapezoid structure can absorb the low frequency electromagnetic (EM) waves and the metallic fishbone structure can absorb the high frequency EM waves. Two absorption bands are respectively in C and Ku bands. The FSS can modulate the passband characteristic of the metallic trapezoid structure and metallic fishbone structure. High-efficiency transmission can be achieved in the middle of two absorption bands. At last, the absorption-transmission-integrated frequency selective structure was fabricated and measured to verify the feasibility of this method. It can be used for the electromagnetic windows of vessels.
关键词： dispersion relation,absorption and transmission,spoof surface plasmon polariton,metallic blade structure
更新于2025-09-19 17:15:36
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Metal Free Acid-Mediated Solid-State Polymerization and Processability of Polymers Based on 3,4-Alkylenedioxythiophenes
摘要： The present article reports metal free acid-mediated polymerization of 3,4-alkylenedioxythiophenes in a solvent free medium and processability of insoluble polymers. It also describes structural variants and functional aqueous dispersions based on 3,4-alkylenedioxythiophenes. Polymers were processed by dispersing the insoluble polymer powders in aqueous media using polymeric aromatic surfactant (polystyrenesulfonate, PSS) and aliphatic surfactant (sodiumdodecylsulfonate, SDS), respectively. The effect of surfactant on particle size, stability, and conductivity of the dispersions was investigated in detail. Polymer particles in SDS-based dispersions tend to agglomerate which resulted enhanced conductivity of the thin films. Electrochemical studies revealed that the polymers are electroactive in nature and are transparent in oxidized state. The electrochromic contrast between the oxidized and reduced states of the polymers was in the range of 40–46%.
关键词： ProDOT,aqueous dispersion,3,4-ethylenedioxythiophene,PEDOT:PSS,conjugated polymers
更新于2025-09-19 17:15:36
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[IEEE 2018 IEEE International Conference on Computational Electromagnetics (ICCEM) - Chengdu (2018.3.26-2018.3.28)] 2018 IEEE International Conference on Computational Electromagnetics (ICCEM) - Studies on Surface Plasmon Dispersion Theory on the Bilayer Graphene Ribbon Arrays Metasurface
摘要： Graphene surface plasmon polaritons (SPP) provide a promising platform to develop a series of new photonic, plasmonic and optoelectronic devices from terahertz to optic spectrum owing to its excellent properties. In this paper, a new kind of graphene metasurfaces, i.e., bilayer graphene ribbon arrays separated by a dielectric gap is proposed. The general dispersion theory of SPP mode on the structure is investigated by a modal expansion method. Solving field expressions on different regions and using proper periodic boundary conditions, the analytical dispersion expressions of SPP mode are obtained on the bilayer graphene ribbon arrays for the first time. With this result, the SPP characteristics of dispersion and propagation loss can be calculated and analyzed with graphene and structural parameters. The proposed SPP modes on the bilayer graphene ribbon arrays metasurface can open up new ways to develop some low-loss sub-wavelength plasmonic waveguide, planar retroreflectors and the enhanced terahertz radiation source.
关键词： surface plasmon polaritons,bilayer graphene ribbon arrays,periodic boundary,dispersion theory
更新于2025-09-19 17:15:36
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Dispersed Nano-MOFs via a Stimuli-Responsive Biohybrid-System with Enhanced Photocatalytic Performance
摘要： MOF-based heterogeneous catalysts with enhanced dispersibility in solution are highly promising for liquid-phase catalysis yet the preparation remains a great challenge. Herein, via introducing responsive polymer-functionalized hollow pollen pivots, a general strategy toward preparing MOF@Pollen composites with adjustable dispersibility, environment-responsive activity and significantly enhanced liquid-phase photocatalytic performance is presented.
关键词： switchable catalysis,nanoMOFs,stimuli responsive polymer,dispersion
更新于2025-09-19 17:15:36