Session Index

In this report, the yellow-green micro-LEDs were fabricated, furthermore, through atomic layer deposition technology the leakage current was reduced. Moreover, a nanoporous GaN distributed Bragg reflector was also introduced to mitigate the quantum confined Stark effect, thereby improving the bandwidth and light extraction efficiency of the device. The device exhibits the highest -3dB bandwidth up to 442 MHz and a data transmission rate of 800 Mbit/s with on-off keying modulation, realizing a light illumination with a high data rate for visible light communication application.

  Preview abstract

The optimal operation condition of amplifier-free violet laser diode is achieved to successfully demonstrate over 30-cm BtB VLC transmission carrying 19.5 Gbit/s 32-QAM-OFDM signals by applying a pre-emphasis algorithm.

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The electro-optical effect of the Mach-Zehnder modulator (MZM) is used to modulate the optical signal, and the high-frequency signal is used to increase the variation of the depletion region, thereby improving the modulation efficiency, reducing the bias voltage, and reducing the power loss. Operate at the best bias voltage point to get the best signal clarity and transmission efficiency after inputting the signal at 25 Gbaud 16 QAM-OFDM.

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The splitting of transverse modes causes mode-beating noise (MBN) of 850-nm multi-mode (MM) vertical-cavity surface-emitting laser (VCSEL) in the noise spectrum at 13 GHz and 33 GHz. The MBN degrades the surrounding sub-carriers signal noise ratio (SNR) and increases the overall noise amplitude. The MBN impacts the SNR, eye height of 850-nm MM VCSEL carrying 50-Gbit/s NRZ-OOK, and degrade the maximum transmission data rate.

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Optical interconnects have attracted great interest in recent years for use in short-reach communication links in high-performance electronic systems such as data centres, data storage systems and supercomputers. Optical links provide significant performance advantages over conventional electrical interconnects, namely, higher bandwidth, lower power consumption at high data rates, immunity to electromagnetic interference, increased density and relaxed thermal management requirements. Flexible multimode polymer waveguides are particularly for use in board-level interconnects as they allow cost-effective formation of optical backplanes and high-speed chip-to-chip optical links directly integrated onto conventional printed circuit boards (PCBs).

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A novel In0.52Al0.48As based avalanche photodiode (APDs) is demonstrated for 106 Gbit/s PAM-4 applications. With a 14 um diameter, we can achieve high bandwidth (32GHz), high-responsivity (2.3A/W) with low dark current (200nA), high gain bandwidth product (GBP) 270 GHz and high saturation power under 11mA photocurrent at 0.9 Vbr operation.

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We demonstrate a long short term memory neural network (LSTMNN) based visible-light-positioning (VLP) system to enhance the positioning accuracy. Different LSTMNN parameters are discussed to optimize the VLP system.

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In this experiment, UV-curable resin combined with a new type of curing method is used to make the optical fiber lens with a special structure. The curing time and the amount of coating are used to adjust the radius of curvature and the size of the lens, then the coupling efficiency with the silicon photonics chip is measured in the end.

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We present a Si photonics (SiPh) mmWave-over-fiber antenna module for 5G fiber-wireless communication. The antenna module consists of silicon photonics transceivers, CMOS millimeter-wave circuits and phased array antennas, heterogeneously integrated on a PCB. We evaluated the system performance by transmitting a 28GHz, 16-QAM OFDM signal through a fiber-wireless system. Experimental results show that the EVMs are 10% and 13% for the downlink and uplink, respectively.

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Coupling control of microresonators is critical for integrated photonics when small gap in-between the bus- and resonator-waveguides are necessary to achieve efficient coupling. To alleviate the fabrication restrictions on the pitch resolution, we proposed a novel method, double-patterning, for realizing a sub-micron gap by the traditional, low-cost contact UV lithography. The fabricated resonators show high extinction ratio up to 8 dB, providing the accessibility of efficient coupling with low-cost, mass-productive fabrication.

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We demonstrate for the first time laser-powered silicon photonics circuit using a CMOS photovoltaic power converter. The optical transmission of silicon Mach-Zehnder interferometer based optical switch was finely tuned by adjusting the illuminating light intensity onto the photovoltaic cells. This proof-of-concept demonstration verifies the feasibility of the proposed scheme for all optical control silicon photonics applications.

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The cross-coupling reduction between array waveguides can lower the crosstalk and enlarge a field of view. A 16-channel optical phased array built with semi-isolated waveguides experimentally demonstrates the full horizontal and vertical widths at half maximum as 2.16 and 1.98 degrees, respectively. Moreover, the side mode suppression ratio achieves 18 dB, which is superior to previous works in a 16-channel optical phased array. In the field of view, the horizontal angle is greater than 60 degrees, and the vertical one can achieve 0.1025 degrees per nanometer.

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We demonstrate the first silicon photonics driver chip that employs thermal-optic phase shifters for interferometric fiber optics gyroscopes (IFOG). This chip occupies only an area of 1.1 mm2, and successfully drives an IFOG system with a scale factor accuracy of 1.42% under ±1000 deg/hr rotational rate.

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In this work, we propose the design of bus waveguide to enhance the coupling strength between the bus- and resonator-waveguides. By introducing the taper structures at the coupled regime, we successfully demonstrate high coupling efficiency with an enhancement factor up to 7.1. Without the need for a small gap between bus waveguide and micro-cavity, this taper design with cost-effective, mass-productive i-line lithography offers potentials in nonlinear and quantum photonics, relying on strong/over-coupling.

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The development of silicon photonics coherent transceivers has progressed rapidly in recent years mainly due to their technological advantages. In this talk I will review some of the recent technological breakthroughs and present some of our own works conducted by our team members at NYCU and NCU.

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A new scheme of buried heterostructure (BH) waveguide laser defined by impurity-free vacancy diffusion (IFVD) quantum well intermixing (QWI) has been demonstrated. A stripe of SiO2 pattern was used for local QWI. A 110 nm blue shift by QWI has been attained to form a 3 μm wide BH waveguide with transmission loss of 16.8 cm-1, enabling the CW lasing performance. Output power of >2 mW in 1490 nm regime has been found in Fabry-Perot laser structure.

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The signatures of high channel resolution (5 GHz), compact size (3.5 mm2), low loss (2.5 dB), low crosstalk (-12.5 dB), and simplified control make the cascaded Mach-Zehnder interferometer a promising solution for frequency measurement applications.

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An integrated FSO-5G NR sub-THz link through a cross-media of 20 km SMF, 500 m optical wireless, and 0.5 m RF wireless is proposed and successfully implemented. 5G NR communication operates effectively with four sub-THz frequencies of 150, 175, 200, and 225 GHz. Each sub-THz frequency carries a 25-Gbps 32-QAM-OFDM signal. By transmitting four 5G sub-THz signals, an integrated fiber-FSO-wireless link with high aggregate data rates of 100 Gbps (25 Gbps × 4) is realized.

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We review emerging technologies including radio-over-fiber and photonic-assisted wireless communication systems, new radio access network architecture design and performance optimization, and enhanced radio access technologies for 6G mobile communications.

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A silicon photonics integrated 16x64 optical phased array (OPA) enables wide-angle beam steering by using optical switches to switch 16 1x64 OPAs, each covers a different steering angle. The measurement demonstrated that the voltage required to switch the different sub-OPAs is < 3V, and the measured far-field patterns confirm the successful switching to the OPAs and cover different beam steering angles.

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In this study, chromium doped yttrium garnet(Cr4+:YAG) thin film was synthesized by sol-gel method. The XRD pattern of the Cr4+:YAG thin film exhibited the YAG phase, and then the fluorescence showed the spectrum of 1200-1600nm as same as a commercial Cr4+:YAG crystal rod. This Cr4+:YAG thin film would be used in silicon photonic chip for the next-generation optical amplifier.

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We propose power-link budgets of 10-Gbps 1000-km satellite laser communication. The Directly
Modulated Laser (DML) nonlinearity comparison of orthogonal frequency-division multiplexing (OFDM) and
single carrier (SC) signals is invesigated. With Volterra and machine-learning nonlinear compensation, the
power-link budget achieve up to 74 dB.

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This study employs a single neural-network-based nonlinear equalizer in a 3×3 MIMO
V-band RoF system for the first time. Experiment results demonstrate >30% improvement in data
rate and >100-Gbps wireless transmission over 100 m.

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In this study, we investigate the cryogenic characteristics of 850 nm datacom vertical-cavity surface-emitting lasers (VCSELs). The light-current-voltage (L-I-V) and the spectral characteristics of the 850 nm VCSELs at various temperatures are studied at 80, 170 and 298 K. Higher material gains and lower optical losses boost the optical output powers and extend the operating currents at lower temperatures. VCSELs also suffer from a significant increase in lasing threshold due to misalignment of the Fabry–Perot (FP) dips.

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For high-performance photonic integrated circuits, reducing bending loss of bent waveguides is a major issue. We design and optimize the performance of silicon bent waveguides by using different window functions, which vary not only bent waveguide radius but also waveguide width. Comparing various bent waveguides using different window functions to the conventional bent waveguide with constant radius and width, the bending loss can be reduced from 0.485 dB to 0.22 dB by optimizing the performance of bent waveguide using 2x trapezoid window function.

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This article first explains general requirements of optical add-drop multiplexing network and describes some technical issues to realize their simple networks. Then, some standardization activities on the optical requirements in a small area are listed and discussed. With surveyed results, in the small area, multi-mode fiber with 800, or 1300 nm band can be used for actual realization with cost effectiveness. Especially, parameters of short 100 Gb/s coarse WDM usage around 900 nm might be powerful candidates if commercially available devices will be used.

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High-performance planar-type InGaAs/InP avalanche photodiode (APD) with single guard ring was fabricated and characterized. Biasing at 0.9 breakdown voltage and room temperature, the dark current of 7.58 nA, multiplication gain of 10.5, capacitance of 0.52 pF, f3dB of 6 GHz, and the gain-bandwidth product of 72 GHz were obtained simultaneously in this work.

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We present an image-resolved approach to calibrate and correct phase errors of Mach-Zehnder-interferometer-based (MZI-based) programmable photonic integrated circuits. Via integration of grating couplers to tap waveguide power in the circuits, we can capture the phase information of key MZI elements in the circuits by investigating the light emitted from the grating couplers through an external infrared camera. All the thermo-optic phase tuners and the infrared camera are interfaced with a LabVIEW program, which can build a large-scale software-defined photonic integrated circuits.

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5G sub-6 GHz/MMW signal transmission over two-way phase-modulated fiber- FSO-wireless links employing remotely injection-locked DFB LDs as transceivers is proposed and successfully achieved. It shows a promising link because of its advancement for incorporating fiber trunk with FSO-5G wireless feeder, and also its advancement for adopting remote injection locking DFB LDs as transceivers to afford two-way 5G emerging services and applications.

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A simple, low-cost, single-longitudinal mode, C-band narrow-linewidth optical fiber laser is presented based on the methodology of the Rayleigh backscattering. In this paper, a 1552 nm fiber ring laser is developed, and single-mode fiber is added to compress the line width. The laser linewidth is 1.46 kHz. The optical signal-to-noise ratio is 59.86 dB, and the output power is 9.3 mW. The result shows that the proposed architecture can easily achieve single longitude-mode output by controlling the variable optical attenuator.

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In this study, we present a high-efficiency InGaN red micro-LED fabricated by the incorporation of the superlattice structure (SL), atomic layer deposition passivation, and a distributed Bragg reflector (DBR), exhibiting maximum EQE of 5.02% with a low efficiency droop corresponding to an injection current density of 112 A/cm2.

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We employed a cascaded Mach-Zehnder interferometer for optical interleaving and an array of racetrack ring resonators for optical channelization. Their combination leads to a 100-GHz spaced wavelength (de)multiplexer for CW-WDM with an optical crosstalk as low as -24 dB.

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We demonstrate a “III-V photodiode over silicon grating coupler (PD-over-GC)” device concept that enables an overall responsivity of 0.964 and 0.367 A/W for 1D and 2D grating coupler, respectively. This is attributed to the fact that the upward optical directivity of 1D (2D) grating coupler achieves 0.9 (0.5), and the III-V photodiode chip accepts a wide range of optical incidence.

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We propose a high-efficiency electro-optically tunable LiNbO3 microdisk resonator using graphene electrodes and three-period outside-ring electrode design. The use of ultra-thin, transparent graphene electrodes not only increases the transmission of the resonant field but also reduces the device fabrication complexity and the fabrication cost. Besides, the proposed three-period outside-ring electrode design can avoid the cancellation of electro-optically induced phase and increase the electro-optic tuning efficiency. The electro-optic tuning rate of the proposed LiNbO3 microdisk resonator is as high as 9.92 pm/V for the TE mode.

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The electro-absorption modulated laser (EML) are now widely used in the high speed transmission, because of its compactness and large bandwidth for transmission at very high data rate. We utilize the heterodyne detection technique to characterize the influence of low frequency drop for an EML. This method provides high resolution in the frequency domain and the measured responses contain both the amplitude and phase information.

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A low-loss (< 0.9 dB), low-crosstalk (< -17 dB), broadband (1500~1600 nm), and fabrication-tolerant optical mode (de)multiplexer is implemented on silicon-on-insulator. This device would enable a high-speed optical link with the combination of wavelength- and mode-division multiplexing schemes.

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We demonstrate and characterize a wide field-of-view (FOV) visible-light-communication (VLC) system using LED light-panel and long-short-term-memory-neural-network (LSTMNN). At a distance of 1m, FOVs of ±70o and ±60o in horizontal and vertical directions can be achieved respectively.

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In this work, we demonstrate silicon nitride micro-ring resonators with air cladding, hafnium oxide (HfO2) cladding, and SU8 polymer cladding and study the effect on waveguide dispersion. By using atomic layer deposition (ALD) HfO2 as the outside cladding layer, the waveguide dispersion can be tuned less in the normal regime at a wavelength of 1550 nm while polymer cladding provides the waveguide dispersion from anomalous to normal.

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We demonstrate the nanostructural reflective polarization converter in silicon waveguide. The reflection of the device is 93.1% when the conversion length is 9.21um with 50 periods. The ultra-wide band width is 170nm at the central wavelength of 1.55um and it covers from 1.45um to 1.62um.

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To mitigate the thermal rollover in vertical-cavity-surface-emitting-lasers (VCSELs), gating-pulse operation with long turn-off time is proposed for the time-of-flight (TOF) sensing application. The rise and fall times can be reduced by >48%.

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We propose flexible integration of groove process to passively edge-couple the optical fibers with on-chip integrated waveguides. By fabricating U-grooves before the waveguide formation, this groove-first process provides a universal platform for hybrid, large-scale photonics.

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In this study, a simple-structured one-dimensional GMR grating that utilizes thin-film properties to enhance FOM is proposed. The electric field intensity in the grating is simulated to evaluate the enhancement of FOM. The waveguide grating structure achieves an extremely high FOM of 839666. A high-performance RI sensor in the near-infrared spectral range is achieved by modifying the geometric parameters. This easy-to-fabricate GMR-based all-dielectric sensing device holds great promise for realizing high-performance and compact broadband RI sensors in biochips, electronic tongues, electronic noses, and so on.

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In this study, we demonstrated a robust terahertz communication system and analyzed the received energy. The result shows the signal-to-noise ratio of the received signal and the system’s channel capacity. The outcome gives the direction of construction and improvement of the broadband terahertz communication based on radio-over-fiber.

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Since optical limiting can be a bottleneck of device performance, accurate characterization of silicon waveguides for high optical power is now vital for modeling optical-powerconcentrated Si-Ph chips. We report the performance of our optical coupling machine and study the nonlinear loss of silicon waveguide with high power continuous-wave-(CW) 1.31 μm wavelength light sources. Detailed studies will be discussed in the conference.

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We demonstrate a modified and improved equivalent small-signal model of External Modulated Laser (EML), which can be used as high speed transmission model for estimating the distributed components of the device. The large-signal circuit model for fully describing the transfer function of EML is also included in this design. By the curve fitting of measured responses to extract device values of the equivalent circuit, the simulation can fit quite well with the measurement results for the EML at various bias voltages.

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The terahertz frequency band is predicted to be the dominant spectrum used in wireless communication in the next generation. Due to its massive unutilized bandwidth, it can be used to transfer massive volumes of data in a brief period of time. This study establishes an optical-based communication system capable of delivering 6G/terahertz signal carriers. This experiment presents the 4 Gbps to 12 Gbps OOK signal transmission through wireless distances shorter than 3 meters when the carrier frequency is set to 125GHz. A UHD video signal is eventually transmitted across the system, revealing the possible applications for high-resolution video streaming.

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In this paper, a two-channel mode division multiplexer (MDM) integrated with SiGe electro-absorption modulators (EAM) on a Si photonics chip is proposed. Directional coupler-based mode multiplexer, two SiGe EAM, and two-dimension grating coupler were integrated in a module, leading to >2.5dB dynamics extinction ratio and overall 100Gb/s non-return-to-zero (NRZ) eye diagram of modulation.

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We demonstrated a fiber-FSO-5G NR MMW/sub-THz convergence system uses single optical carrier modulation to effectively suppress power fading induced by fiber chromatic dispersion and interferences induced by beating between multiple optical carriers, as well as coherent multi-carrier optical beating to effectively eliminate nonlinear noises induced by incoherent multi-carrier optical beating. 20 Gb/s 16-QAM-OFDM in the 50-GHz MMW, 100-GHz sub-THz, and 150-GHz sub-THz bands through the fiber-FSO-5G NR convergence is successfully implemented.

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In this work, we experimentally demonstrated an optical OFDM system with pre-emphasis technique and artificial neural network nonlinear equalizer (ANN-NLE). Baseband signal is pre-emphasized and received signal is equalized by ANN-NLE to combat frequency fading and phase distortion issues. The result showed error-free BER without FEC technique in back-to-back scheme.

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In this study, we developed a mathematical representation of the Mach-Zehnder Modulator (MZM) that can simulate the actual signal using a real-time oscilloscope recording. It is possible to model OOK and OFDM signals and determine the nonlinear impact of MZM on signal, which will be helpful for channel estimation in the Terahertz communication band.

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We demonstrate the higher coupling efficiency and pump signal conversion efficiency (PSCE) by the LHPG system with an AI monitoring system. Compared with the core diameter of 15-µm SMCDCCF, the CE, PSCE were improved by 3.3 times, and gross gain were improved by 1.3 times. By developing a small diameter SMCDCCF is essential for practical use in the next-generation broadband fiber amplifier applications.

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A harmonic microwave down-converter based on stabilized period-one (P1) nonlinear dynamics of
semiconductor lasers subject to external optical injection is proposed and experimentally demonstrated. The
proposed system has advantages of wide tunability, broad conversion bandwidth, and high operating frequency.

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This study implemented a reverse reconciliation scheme with low-density parity-check (LDPC) codes into our quantum key distribution (QKD) simulator to correct the errors generated in the (QKD) used in quantum communication. The results show that the error correction strategy with sparse parity-check matrices defined by IEEE standards satisfies the requirement of reconciliation in differential phase shift QKD.

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Semiconductor optical amplifier (SOA) integrated electroabsorption modulators (EAM) for both high speed and low-pattern dependence modulation has been demonstrated. SOA/EAM integration was realized by impurity-free vacancy diffusion (IFVD) quantum well intermixing (QWI) technology, which is used for matching the bandgap (wavelength) between devices. Therefore, the complementary saturation properties of SOA and EAM in the timely carrier dynamic response can be utilized for pattern insensitive and thus high speed modulation.

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We demonstrate a broadband and steady EDF multiple-ring laser based on the octa-ring design together with Vernier operation for achieving SLM action. The available CW tunability range from 1571.0 to 1613.0 nm in L-band window. Moreover, the related output power, SLM oscillation, OSNR and stability appearances in the laser have been also explored.

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We study the propagation mode of surface plasmon polariton in metallic nanohole. The dispersion relations of SPPs in a nanohole, solved from a transcendental equation, show that SPPs of mode-1 with a propagation length larger than the other modes. When the mode-1 propagates in the nanohole, the normal component of electric displacement on the nanohole’s surface with a helical distribution and the streamlines of Poynting vector exhibit helixes. Additionally, by using COMSOL we investigate the conversion of the helical SPP reaching at the nanohole’s outlet into a spiral SPP propagating outward on the metal film’s interface with the same handedness.

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The modal effective index matching is used to design the waveguide structure through Shortcuts to Adiabaticity, the TE00 mode is matched to the TE11 mode, and the coupling efficiency is 63.6%, the spanning of the supercontinuum generation is observed. Finally, the CCD can observe clearly TE11 modal.

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We design a dual-ring structure with a unpumped EDF saturable absorber (SA) to achieve wide and stable single-mode C- plus L-band EDF laser applying two parallel EDFAs as the gain medium. Here, we also verify the output power, OSNR, tunability, and stability of the proposed EDF ring laser.

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In the study, we demonstrate a hybrid self-healing FSO-WDM-PON system. Here, the available WDM channels in C- and L-bands are applied for baseband and FSO access, respectively. Besides, to prevent the fiber breakpoint in baseband fiber network, the WDM network also can provide the re-routing fiber path for reconnection.

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We have developed a simulation model for characterizing DWDM gain flattening Erbium doped fiber amplifiers with transient gain control. The dynamic gain in the presence of channel add-drop under both feed-forward/feed-back pump control for achieving a constant gain can be simulated for analyzing the amplifier performance. The simulation results indicate that the EDFA transient gain excursion caused by channel add-drop can be effectively suppressed by the combinational usage of electrical feed-forward and feed-back mechanisms. Our modelling approach is novel in the respect that the feed-forward/feed-back transient gain control is integrated with the EDFA dynamic simulation for the first time.

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We have successfully demonstrated the possibility of implementing an integrated mode division multiplexer/de-multiplexer by utilizing an apodized 2D slanted grating coupler to multiplex/de-multiplex one fundamental (LP01) and one higher order (LP11) mode for each polarization between a few-mode fiber and the SOI chip. The whole device is composed of three parts: the 2D grating coupler, the tapered waveguides, and the MDM waveguide-type directional couplers. The design is optimized and manufactured by adopting the SOI thickness of 220nm with the 500nm top oxide and the 2 μm bottom oxide. Experimental results for proof of the concept are reported.

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Orthogonal frequency-division multiplexing (OFDM) is commonly applied for visible light communication (VLC) to more efficiently use the limited bandwidth of a light emitting diode (LED). The operating point of the LED must be optimized to reduce the nonlinear distortion. We show that the optimal operating points are different for users at different regions. For a bit error rate (BER) criterion around 10^-3, the power penalty for users (respectively optimized) at the center and edge regions is much reduced. The optimal operating point for the edge users could be more tolerant to voltage errors and results in more uniform BER performance.

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A method to fabricate novel liquid crystal fiber device is proposed by combining liquid crystals (LCs and hollow core fiber (HCF), in which a liquid crystal long period fiber grating (LC-LPFG) is fabricated using Surface Polymer Stabilized Alignment (SPSA) technique. Owing to the photo-polymerization conditions significantly influence the morphology of fiber grating structure, the influence of UV exposure time and curing voltage on the propertied of LC-fiber were studied. Based on the experimental results, we observed the threshold voltage and saturation voltage of LC-LPFG decreased with the increase of exposure time and curing voltage, respectively

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The radiation efficiencies of enhanced coupling strength Gratings at first Bragg are calculated. The thicknesses of dielectric waveguides are increased to obtain accurate results of the radiation power.

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We propose a broadband polarization beam splitter based on a decoupled symmetrical directional coupler. TM mode will be decoupled at finite separation between two symmetrical rib waveguide. This design is proposed to be implemented using TSRI IMEC-SiPh process technology. Numerical simulations show that the proposed PBS has a broad bandwidth (~100 nm) with large extinction ratio (> 13.5 dB).

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Adiabaticity engineering in multi-parameter is applied to design an ultra-broadband silicon polarization independent 3-dB coupler. Adiabaticity engineering can shrinks the adiabatic device lengths, maintains the advantage of large bandwidth and results in the characteristic of polarization independence in the devices. The total length is 84 um and the device exhibit a bandwidth of over 300 nm.

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In this study, a 3dB power splitter based on a shallow-ridge silicon nitride directional coupler structure is designed, and it exhibits a power splitter ratio that is insensitive to changes in waveguide width and coupling gap. The power splitter using a shallow-ridge waveguide structure exhibits a large fabrication tolerance and can achieve a power splitter ratio close to 1:1 at 1550 nm for TE polarized light.

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The authors utilize the shift-or-shrink (SOS) algorithm to obtain the optimal structural parameters of microlens for maximizing the direct coupling efficiency from a single-mode fiber to an optical channel waveguide. The optimal structural parameters and the corresponding efficiencies are presented in this work.

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A robust optical fiber network architecture for large-scale fiber sensor systems is proposed to remotely monitor the construction safety of buildings or bridges. Benefiting from a self-composed bidirectional device and proper optical routing function, the system manager not only can use each normal optical fiber pathway to deliver detection lightwaves to targeted sensors but also can use each other’s normal pathways as backup links to detect the targeted construction. The proposed fiber sensor network can provide proper self-healing function and simple network structure against one or multiple fiber link failures.

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We employed the plane-wave expansion method to study the dielectric mirror as a semi-infinite two-dimensional photonic crystal in air. Light-line criterion for ambient incidence was applied in the calculations of the projected band structures and the restricted density of states. We further employed the equivalent refractive index model to obtain the angular band diagram which is in good agreement with the result obtained by transfer matrices.

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Gold nanoparticles of size 60-200 nm are coated on a bilayer HfO2/Al2O3 dielectric thin film fabricated on a quartz substrate. Mode coupling between the localized surface plasmon resonance and cavity coupling enhanced by Fabry-Pérot interference are discussed. Full-color spectral tuning effects are verified with simulation based on a finite-difference time-domain calculation and with a home-built imaging spectral measurement system.

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We derived the formula of the guiding power density to analyze the forbidden region of the local Kerr-type nonlinear slab left-handed metamaterial (LHM) optical waveguide structure. The numerical results show that the forbidden region always exits in the proposed optical waveguide structure.

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In this paper, we propose and numerically investigate all-optical plasmonic filter based on nano-disk cavity structures. We used waveguides and filled with optical nonlinear materials nano-disk resonators to construct all-optical filter based on MIM waveguide structure. The dielectric constant of Kerr nonlinear medium in the resonator is changed by varying the pump light and the signal transmission can thus be controlled. The performance of the proposed all-optical filter was analyzed by the finite difference time domain (FDTD) method.

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we propose an high efficiency polarization beam splitter with directional coupler based on subwavelength-grating waveguide and slot waveguide on a standard silicon-on-isolator platform. Assisted by a tapered subwavelength grating waveguide and a slot waveguide, the working bandwidth of the directional-coupler-based PBS covers the entire O-, E-, S-, C-, L- and U-bands and the coupling length is only 4.6 µm.

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In this work, we propose a broadband silicon nitride polarization beam splitter. This polarization beam splitter that is based on asymmetric directional couplers exhibits a broadband operation with an extinction ratio of greater than 10 dB.

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Nowadays, transition metal chalcogenides (TMCs) semiconductor materials have attracted a lot of attention in recent research due to their unique characteristics in photonics and electronics applications. Hydrothermal method synthetization technique for CuS and CuSe might contain high impurity while compare with other method. To obtain high crystallinity and purity crystal, we use chemical vapor transportation (CVT) as the synthesize technique. This paper presents the optical iridescence characteristics of CuS and CuSe. We observed two different types of μ-photoluminescence spectra for both crystals. Our analyses further discussed on grating effect which produce the white light and its separations.

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We demonstrate fronthual links with delay-division-multiplexing 14-GHz bandwidth 64-QAM OFDM for 128 RF-chain signals. The corresponding CPRI-based capacity is 860.16 Gb/s.With I/Q Volterra nonlinear compensation, EVMs can be improved from 7.5% to 6%.

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We propose a new scheme of multi-perimeter-zone fiber-optic intrusion detection system with Fabry-Perot interferometers used as disturbance sensors in a single fiber line. An outdoor test is carried out for a four-perimeter-zone system with an outcome of extremely high alarm rate upon intrusion, and a zero false alarm rate in the case of non-intrusion.

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An underwater wireless optical communication (UWOC) system was proposed using a 450nm blue laser with 1.25 Gbps OOK modulation. The environmental effect, such as turbulence in different water densities, was measured at a 3-meter distance. The maximum BER that our system can reach in the 1.03 seawater density was 4.85x10-6 at -7.4 dBm. The water density can affect the system to obtain a higher BER floor, while turbulence affects the higher deviation in the BER performance.

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We demonstrated a 1064 nm band semiconductor optical amplifier (SOA) based fiber ring laser in 1064 nm band. The combination of a high-power Ytterbium-doped fiber amplifier (YEDFA) is developed with the maximum output power of 2.033 W. The pulse repetition rate, optical signal to noise ratio, pulse energy and peak power are 181.81 kHz, 34 dB, 11.23 μJ and 11.12 W, respectively. The total output power reaches 1.269 W in 5A current. The 1064 nm fiber laser source is suitable for Raman sensing and medical treatment by using master oscillation power amplifier (MOPA) scheme to increase the optical power.

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