- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Grating coupler with reduced back reflection using λ/4 offset at its grating sub-teeth
摘要： We demonstrate a grating coupler with reduced back reflection on silicon-on-insulator (SOI) platform. Each grating tooth of the grating coupler is uniformly divided into multiple sub-teeth with λ/4 offset between two adjacent sub-teeth, reducing the Fresnel reflection from interfaces between core and cladding materials in transmission direction. The back reflection can be theoretically suppressed from ?12 dB to below ?30 dB for a focusing grating coupler working at TM polarization. Experimental results show that the effect of Fresnel reflection on transmission spectrum of the proposed grating coupler is significantly reduced compared to conventional grating coupler. Furthermore, a microring resonator using the proposed focusing grating coupler to couple light into and out of waveguide is fabricated. The measured spectra show that fluctuations on transmission spectra of the ring resonator are effectively suppressed, especially for the drop-port, a well-shaped resonance peak is clearly observed, making the resonance wavelength easily distinguishable, which is highly required in sensing applications using wavelength interrogation.
关键词： Fresnel reflection,grating coupler,waveguide,ring resonator
更新于2025-09-23 15:23:52
-
[IEEE 2018 IEEE PELS Workshop on Emerging Technologies: Wireless Power Transfer (WoW) - Montréal, QC, Canada (2018.6.3-2018.6.7)] 2018 IEEE PELS Workshop on Emerging Technologies: Wireless Power Transfer (Wow) - Analysis of the Effect of the Shielding on Coils in the Wireless Power Transfer System Applied in Trams
摘要： As an important component of Wireless Power Transfer (WPT) system for transmitting energy, the coupler, composed of coils and shielding, is worth studying parameters effect on the system performance. When the WPT system is applied to trams, the primary coupler is installed between two rails, and the secondary coupler is installed at the bottom of the carriages. The magnetic field produced by the coupler has an effect on carriages and rails, which need to be analyzed. In this paper, the influences of coupler parameters on system performance are analyzed. The mathematical model of coupler is found. The measure to improve the metal influences of the vehicle body is put forward, and the correctness of the analysis is verified through preliminary experiments.
关键词： Modern tram,Mathematical Modeling,Wireless Power Transfer,Coupler
更新于2025-09-23 15:23:52
-
Performance evaluation of mode group power coupling for short reach SDM
摘要： The profound understanding of mode coupling in spatial multiplexed optical systems is required for performance optimization purposes. In this contribution different optical coupler technologies are compared with respect to their bit-error rate (BER) performance as multiplex devices in a (2 × 2) multiple-input multiple-output (MIMO) environment. Therefore, the power coupling coefficients between mode groups for all testbed components are determined at 1327 nm with a method based on impulse response measurements. This method and its refinements are presented in this work. By taking the obtained power coupling coefficients, the MIMO impulse responses are simulated and the corresponding BER performance for different launch parameters is studied. The simulation setup includes single-mode fiber (SMF) to multi-mode fiber (MMF) splices aligned with different radial eccentricities for mode group specific excitation, different multi-mode couplers for mode multiplexing, a 1 km OM4 grade MMF and a multi-mode fusion coupler for demultiplexing. Here, the setup with the customized fusion coupler shows the best BER results in comparison to other coupler technologies. In addition, the optimal choice of the SMF to MMF launch eccentricity highly depends on the implemented coupler technology. Particularly, deviations of 2 μm from the optimal launch setup can lead to a tenfold increase in the BER. It is noteworthy, that the optimal setup does not always include the center launch condition.
关键词： Multi-Mode MIMO,Mode Group Power Coupling,Coupler Technology
更新于2025-09-23 15:23:52
-
Analyzing the effect of higher order nonlinearity on dispersion relation and optical multistability generation in oppositely directed coupler
摘要： We report the influence of higher order nonlinearity on dispersion relation and multistability in oppositely directed coupler with negative index material channel. The study shows that the high intensity electric field shifts the photonic bandgap down in energy. When the positive index material channel of the coupler is influenced by quintic nonlinearity the group velocity of upper branch of dispersion curve (δ–q curve) falls to zero in positive q region and the loop in the lower branch shifts to positive q region. But the minima in upper branch and loop in the lower branch are observed at negative q region when the negative index material channel is influenced by χ(5) nonlinearity. As the curvature of the dispersion relation determines the group velocity dispersion the study report the possibility for dispersion engineering in oppositely directed coupler. Also we observed that the quintic nonlinearity enhances formation of multi stable states.
关键词： Oppositely directed coupler,Multistability,Optical switching,Negative index materials
更新于2025-09-23 15:23:52
-
High-Performance Tunable Narrowband SIW Cavity-Based Quadrature Hybrid Coupler
摘要： This letter presents, for the first time, a tunable narrowband substrate integrated waveguide (SIW) cavity-based quadrature hybrid coupler. Four high-quality factor (Q) SIW evanescent-mode cavity resonators are employed in the design and tuned using piezoelectric actuators. This allows the proposed coupler to have wide spurious-free range (SFR), low-power consumption, and high-power handling capability compared to other tunable planar couplers. The coupler can be tuned starting from 1.32 to 2.22 GHz with a measured insertion loss range from 1.29 to 0.7 dB. Over the full range, the measured 3-dB fractional bandwidth ranges from 5% to 18% while the phase error (∠S21 ? ∠S31) absolute bandwidth measured ±5° ranges from 40 to 82 MHz with an amplitude imbalance range between 1 and 0.3 dB. The measured reflection and isolation are better than 12 and 17 dB, respectively. Moreover, the coupler has a measured SFR of 5.1–3 fo (lowest–highest frequency).
关键词： tunable quadrature hybrid coupler,Evanescent-mode (EVA) cavity,tunable resonators
更新于2025-09-23 15:22:29
-
A Versatile Silicon-Silicon Nitride Photonics Platform for Enhanced Functionalities and Applications
摘要： Silicon photonics is one of the most prominent technology platforms for integrated photonics and can support a wide variety of applications. As we move towards a mature industrial core technology, we present the integration of silicon nitride (SiN) material to extend the capabilities of our silicon photonics platform. Depending on the application being targeted, we have developed several integration strategies for the incorporation of SiN. We present these processes, as well as key components for dedicated applications. In particular, we present the use of SiN for athermal multiplexing in optical transceivers for datacom applications, the nonlinear generation of frequency combs in SiN micro-resonators for ultra-high data rate transmission, spectroscopy or metrology applications and the use of SiN to realize optical phased arrays in the 800–1000 nm wavelength range for Light Detection And Ranging (LIDAR) applications. These functionalities are demonstrated using a 200 mm complementary metal-oxide-semiconductor (CMOS)-compatible pilot line, showing the versatility and scalability of the Si-SiN platform.
关键词： transceiver,silicon photonics,Kerr nonlinearity,optical phased array,Coarse Wavelength Division Multiplexing (CWDM),multiplexing,LIDAR,silicon nitride,beam steering,frequency comb,grating coupler
更新于2025-09-23 15:22:29
-
Design of a Low-Cost Microstrip Directional Coupler with High Coupling for a Motion Detection Sensor
摘要： A coupled-line coupler based on the asymmetric cascade connection of two coupled line sections is used to achieve a high coupling factor using low-cost material and technology in the X frequency band, and its performance is compared with a standard quarter-wave, coupled-line coupler, showing an increase in the coupling factor of about 3 dB. The proposed coupler can be effectively used in a Doppler motion detection sensor, due to its strong coupling and relatively high isolation. The coupler is designed through a simple, yet rigorous, equivalent circuital model. Then, an optimization procedure was performed using the commercial software Ansys HFSS in order to compensate for losses and second order effects. A prototype of the designed coupler was realized, and the measured data show very good agreement with simulations.
关键词： coupled lines,directional coupler,motion detection systems
更新于2025-09-23 15:22:29
-
[IEEE 2017 14th IEEE India Council International Conference (INDICON) - Roorkee (2017.12.15-2017.12.17)] 2017 14th IEEE India Council International Conference (INDICON) - Design and study of Cylindrical RF pill box window for 100 GHz BWO with Single side Tapered Output Coupler
摘要： The paper represents the design and implementation of a Silicon Pillar Bow Windmill used in LED output coupler at a frequency of 100 GHz with cylindrical waveguides. The design and simulation have been carried out using CST microwave studio. The designed windmill has a circular aluminum disc with a thickness of 3.19 μm and radius of 2500 μm. The circular disc is sandwiched between two circular waveguides. The designed windmill has been simulated and the return loss and insertion loss are obtained as -22.38 dB and -0.000723 dB respectively at this frequency. The designed windmill has good performance and can be used for low and medium power microwave applications.
关键词： Silicon Pillar Bow Windmill,LED output coupler,insertion loss,CST microwave studio,return loss,cylindrical waveguides
更新于2025-09-23 15:22:29
-
Sensing of airborne molecular contaminants based on microfiber coupler with mesoporous silica coating
摘要： Airborne molecular contaminants (AMCs) are critical issues for the performance of optics in high power lasers (HPLs). In this work we demonstrate an AMCs sensor based on an optical microfiber coupler (OMC) with mesoporous silica coating experimentally. AMCs adhered on the mesoporous silica coating modifies the surrounding refractive index (RI). Using Beam Propagation Method (BPM), the proposed structure was analyzed to demonstrate the feasibility of AMCs sensing. By coating a mesoporous silica layer on the surface of sensing area, the proposed structure was able to operate as an AMCs sensor. By monitoring the spectral shift in the wavelength domain, the sensor was shown to be capable of detecting concentration of AMCs. The experimental results show that the sensitivity of the sensor is concentration-dependent. The maximum sensitivity of 0.541nm/(mg/m3) is achieved. The detected signal is found to be proportional to AMCs present.
关键词： Airborne molecular contaminants (AMCs),Beam propagation method,Optical microfiber coupler (OMC),Evanescent field
更新于2025-09-23 15:22:29
-
[IEEE 2018 IEEE 15th International Conference on Group IV Photonics (GFP) - Cancun (2018.8.29-2018.8.31)] 2018 IEEE 15th International Conference on Group IV Photonics (GFP) - Optimization of a Polarization Beam Splitter for Broadband Operation using a Genetic Algorithm
摘要： We present a design method for a polarization beam splitter for broadband operation based on a genetic algorithm (GA). The devices are segmented into short sections, where the geometric parameters for each device are determined using a GA.
关键词： genetic algorithm,silicon photonics,directional coupler,broadband,optimization,beam splitter
更新于2025-09-23 15:22:29