- 标题
- 摘要
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- 实验方案
- 产品
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Spatial-mode switchable, multi-wavelength all-fiber erbium-doped fiber (EDF) laser based on low modal crosstalk mode multiplexer/demultiplexer (MUX/DEMUX)
摘要： We experimentally demonstrate an all-fiber erbium-doped fiber ring laser based on a Sagnac interferometer with a low modal crosstalk mode multiplexer/demultiplexer (MUX/DEMUX). Three linearly polarized (LP) modes are generated by mode MUX/DEMUX, which consists of cascaded mode-selective couplers. The proposed fiber laser can simultaneously achieve spatial-mode switching and multi-wavelength tuning. In the experiment, single-, dual-, and triple-wavelength lasing outputs for LP01, LP11, LP21 and hybrid modes are obtained. The stabilities for LP01, LP11, LP21 and hybrid modes are investigated in more than 20 min, 16 min, 12 min and 16 min, respectively. Moreover, the mode intensity profiles, the OSNRs of the lasing output and the slope efficiencies are also measured.
关键词： multi-wavelength fiber laser,mode multiplexer/demultiplexer (MUX/DEMUX),spatial-mode switching,Sagnac interferometer
更新于2025-11-28 14:23:57
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Integrated 25?GHz and 50?GHz spectral line width dense wavelength division demultiplexer on single photonic crystal chip
摘要： We propose a new integrated demultiplexer model using the two-dimensional photonic crystal (2D PC) through the hexagonal resonant cavity (HRC) for the International Telecommunication Union (ITU) standard. The integrated model of demultiplexer for both 25 GHz and 50 GHz has been designed for the ?rst time. The demultiplexer consists of bus input waveguide, drop waveguide, Hexagonal Resonant Cavity (HRC), 6 Air Hole Filter (6-AHF), 7 Air Hole Filter (7-AHF). The 7-AHF is used to ?lter 25GHz wavelength, and the 6-AHF ?lter is used to ?lter 50 GHz wavelength. The Q-factor on the designed demultiplexer is ?exible based on the idea of increasing the number of air holes between drop waveguide and resonant cavity. The demultiplexer is designed to drop maximum 8 resonant wavelengths. One side of demultiplexer is able to drop 50 GHz ITU standard wavelengths, which are of 1556.3 nm, 1556.7 nm, 1557.1 nm and 1557.5 nm, and further the other facet is able to drop 25 GHz wavelengths, which are of 1551.4 nm, 1551.6 nm, 1551.8 nm, and 1552.0 nm. The proposed demultiplexer may be carried out within the integrated dual system. This system is able to lessen the architecture cost and the size is miniaturized substantially.
关键词： Line width,Crosstalk,Cavity,Demultiplexer,Quality factor
更新于2025-09-23 15:21:01
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Tunable Mid-Infrared Graphene Plasmonic Cross-Shaped Resonator for Demultiplexing Application
摘要： In this study, a tunable graphene plasmonic ?lter and a two-channel demultiplexer are proposed, simulated, and analyzed in the mid-infrared (MIR) region. We discuss the optical transmission spectra of the proposed cross-shaped resonator and the two-channel demultiplexer. The transmission spectra of the proposed MIR resonator are tunable by change of its dimensional parameters and the Fermi energy of the graphene. Our proposed structures have a single mode in the wavelength range of 5–12 μm. The minimum full width at half maximum (FWHM) and the maximum transmission ratio of the proposed resonator respectively reached 220 nm and 55%. Simulations are performed by use of three-dimensional ?nite-di?erence time-domain (3D-FDTD) method. Coupled mode theory (CMT) is used to investigate the structure theoretically. The numerical and the theoretical results are in good agreement. The performance of the proposed two-channel demultiplexer is investigated based on its crosstalk. The minimum value of crosstalk reaches ?48.30 dB. Our proposed structures are capable of providing sub-wavelength con?nement of light waves, useful in applications in MIR region.
关键词： resonator,plasmonics,graphene,Fermi energy,demultiplexer
更新于2025-09-23 15:19:57
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Photovoltaic String Sizing Using Site-Specific Modeling
摘要： This paper focuses on electroencephalogram (EEG) manifestations of mental states and actions, emulation of control and communication structures using EEG manifestations, and their application in brain-robot interactions. The paper introduces a mentally emulated demultiplexer, a device which uses mental actions to demultiplex a single EEG channel into multiple digital commands. The presented device is applicable in controlling several objects through a single EEG channel. The experimental proof of the concept is given by an obstacle-containing trajectory which should be negotiated by a robotic arm with two degrees of freedom, controlled by mental states of a human brain using a single EEG channel. The work is presented in the framework of Human-Robot interaction (HRI), speci?cally in the framework of brain–robot interaction (BRI). This work is a continuation of a previous work on developing mentally emulated digital devices, such as a mental action switch, and a mental states ?ip-?op.
关键词： Brain–robot interaction (BRI),mental action EEG switch,mentally emulated EEG demultiplexer,electroencephalogram (EEG) manifestations of mental states and actions,mental state CNV ?ip-?op
更新于2025-09-23 15:19:57
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Plasmonic Demultiplexer With Tunable Output Power Ratio Based on Metal-Dielectric-Metal Structure and E7 Liquid Crystal Arrays
摘要： A novel tunable plasmonic demultiplexer is proposed and numerically investigated by finite element method(FEM). It consists of two half-nanodisk cavities and two sets of E7 liquid crystal arrays which are side-coupled to three metal-dielectric-metal(MDM) waveguides. The demultiplexer can split the input lights into two parts corresponding to port1(1310nm) and port2(1550nm). The Q-factors of port1 and port2 are 54.6 and 36, and the crosstalk values are -20.7dB and -29.9dB, respectively. Obviously, both channels have high Q-factors and low crosstalk value. Moreover, the E7 liquid crystal arrays play a key role in the whole structure, which makes the output power adjustable proportionally by adjusting the applied voltage. This novel feature greatly enriches the function of our demultiplexer. Using the electronical tunable birefringence characteristic of liquid crystal and its arrays structure paves a new way to realize practical on-chip plasmonic system, which can be widely used not only in demultiplexers but also in nanosensors, optical splitters, filters, optical switches, nonlinear photonic and slow-light devices.
关键词： on-chip plasmonic system,demultiplexer,surface plasmon polaritons(SPPs),Metal-dielectric-metal(MDM) waveguide
更新于2025-09-23 15:19:57
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Compact eight-channel wavelength demultiplexer using modified photonic crystal ring resonators for CWDM applications
摘要： An eight-channel wavelength demultiplexer by cascading of ring resonators (RRs) in photonic crystal (PhC) structure is proposed in this paper. In designing of this demultiplexer, we used eight square-shaped PhC RRs with different refractive index (RI) of defect rods to generate a distinctive resonance wavelength. Each PhC RR has a specific resonance wavelength with tuning a variety of design parameters such as RI of a whole, defect and inner rods and radius of defect rods. In operating wavelength of λ0 = 1497 nm, the transmission power and quality factor (Q) of single RR are discovered as 96% and 1000, respectively. The average power transmission, channel spacing, crosstalk and full width at half maximum are found by finite difference time domain method to be about 96 ± 1%, 2.25 nm, ? 35 dB and 1.5 nm, respectively. Simulation outcomes demonstrate that the designed demultiplexer has a proper operation. The footprint of the designed device is about ~ 115 μm2, which makes this device a promising for future photonic integrated circuits.
关键词： Photonic crystal,Square shape ring resonator,Wavelength demultiplexer
更新于2025-09-19 17:13:59
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AIP Conference Proceedings [AIP Publishing THE 2ND INTERNATIONAL CONFERENCE ON APPLIED PHOTONICS AND ELECTRONICS 2019 (InCAPE 2019) - Putrajaya, Malaysia (22 August 2019)] THE 2ND INTERNATIONAL CONFERENCE ON APPLIED PHOTONICS AND ELECTRONICS 2019 (InCAPE 2019) - Design of arrayed waveguide grating (AWG) demultiplexer based PMMA for narrow channel spacing
摘要： Arrayed Waveguide Grating (AWG) based PMMA polymer that functioning as multiplexer/demultiplexer (mux/de-mux) having good potential in WDM system and interferometer optical sensor. Besides, AWG is suitable for larger count optical signals and good filter response devices. AWG demultiplexer based polymer was simulated using Beam Propagation Method (BPM) under TE mode with 1550 nm central wavelength. This work explores the performance of polymer-based AWG with straight waveguide structure that capable to produce 16-channels AWG device for 100 GHz (0.8 nm) channel spacing. The 16-channels AWG based polymer produces low insertion loss of 3.430 dB and low crosstalk of -24.763 dB. The central wavelength for each output port gives almost similar values with the standard ITU-T DWDM wavelength grid with the smallest difference of 0.5 nm. This proposed device also capable to solve the demand on higher channel capacity especially to support internet usage and the needs of the best communication system.
关键词： AWG,PMMA,narrow channel spacing,WDM system,Arrayed Waveguide Grating,demultiplexer
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Novel optical approach for concentrating light in micro-CPV
摘要： This paper focuses on electroencephalogram (EEG) manifestations of mental states and actions, emulation of control and communication structures using EEG manifestations, and their application in brain-robot interactions. The paper introduces a mentally emulated demultiplexer, a device which uses mental actions to demultiplex a single EEG channel into multiple digital commands. The presented device is applicable in controlling several objects through a single EEG channel. The experimental proof of the concept is given by an obstacle-containing trajectory which should be negotiated by a robotic arm with two degrees of freedom, controlled by mental states of a human brain using a single EEG channel. The work is presented in the framework of Human-Robot interaction (HRI), speci?cally in the framework of brain–robot interaction (BRI). This work is a continuation of a previous work on developing mentally emulated digital devices, such as a mental action switch, and a mental states ?ip-?op.
关键词： Brain–robot interaction (BRI),mental action EEG switch,mentally emulated EEG demultiplexer,electroencephalogram (EEG) manifestations of mental states and actions,mental state CNV ?ip-?op
更新于2025-09-19 17:13:59
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Inverse Design of Orbital Angular Momentum Mode Demultiplexer by Combining Wavefront Matching Method and Gradient Descent Algorithm
摘要： The spatial mode demultiplexer is a critical component in the mode division multiplexing communication system, which requires the merits of power-efficiency and low-crosstalk. It has been demonstrated that any unitary transform of spatial modes can be implemented by passing through a succession of phase masks with free-space propagation in between, and the key is to inversely design the phase distribution of each phase mask. One inverse approach is based on wavefront matching method, which is employed in the technique termed multi-plane light conversion (MPLC). This approach enables an efficient optimization of overlap integrals between the obtained modes and the desired modes. However, this method does not have an objective function, meaning that it is incapable of implementing specific optimization. Another approach is based on the gradient descent algorithm, which is flexible in choosing objective functions, while the performance in maximizing overlap integrals is less desirable when compared with wavefront matching method. In this work, we design an efficient orbital angular momentum (OAM) demultiplexer inversely by combining the wavefront matching method and the gradient descent algorithm. Firstly, we employ the wavefront matching method to optimize all the phase masks until convergence. Then, by setting adjacent crosstalk as a part of the objective function, we apply the gradient descent algorithm to further optimize the mode demultiplexing performance. Since the objective function is already close to the local minimum, the subsequent gradient descent process will converge in a few iterations. To confirm this idea, we demonstrate the mode transformation from OAM modes with azimuthal topological charge from l = -3 to l = 3 to displaced Gaussian modes. The configuration including the input and output modes as well as the number and positions of the phase masks are determined with reference to the spiral transformation scheme. By the combinational use of aforementioned methods, we design an OAM demultiplexer that can sort 7 pure vortex modes with 3 phase masks. The designed phase profiles present a similarity to those implemented in spiral transformation, especially for the third phase mask resembling to an elliptical lens. The maximum insertion loss and crosstalk of the device are -0.2 dB and -21.1 dB, with a 5.6-dB improvement in maximum crosstalk resulting from the further gradient descent optimization after wavefront matching.
关键词： Gradient Descent Algorithm,Mode Demultiplexer,Inverse Design,Wavefront Matching Method,Orbital Angular Momentum
更新于2025-09-16 10:30:52
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Design and analysis of a plasmonic demultiplexer based on band-stop filters using double-nanodisk-shaped resonators
摘要： In this paper, a two-channel plasmonic wavelength demultiplexer (PWDM) based on band-stop filters (BSF) using double-nanodisk-shaped resonators is proposed. The structure is numerically simulated using finite difference time domain method. First, a BSF is considered for modeling which supports three modes. Then, the effect of various structural parameters of the proposed PWDM is studied on the transmission properties in detail. The results show that the transmission properties of our PWDM are highly dependent on geometric parameters. The proposed structure provides a single-mode spectrum on each of the output ports with a maximum quality factor as high as 105 (FWHM = 7.7 nm). To this end, we illustrate that the concerning published research in this field, the significant privilege of our proposed PWDM structure is in terms of its good transmission efficiency, lowest FWHM and highest quality factor. Hence, such an arrangement is easy to fabricate and it has the potential for use in all-optical ultra-compact circuits and devices.
关键词： Metal–insulator–metal waveguide,Plasmonic demultiplexer,Nanodisk resonator,Plasmonic filter,Surface plasmon polariton,Finite difference time-domain method
更新于2025-09-16 10:30:52