Weakly-coupled mode division multiplexing(MDM)technique is considered a promising candidate to enhance the capacity of an optical transmission system,in which mode multiplexers/demultiplexers(MMUX/MDEMUX)with low inse...Weakly-coupled mode division multiplexing(MDM)technique is considered a promising candidate to enhance the capacity of an optical transmission system,in which mode multiplexers/demultiplexers(MMUX/MDEMUX)with low insertion loss and modal crosstalk are the key components.In this paper,a low-modal-crosstalk 4-mode MMUX/MDEMUX for the weakly-coupled triple-ring-core few-mode fiber(TRC-FMF)is designed and fabricated with side-polishing processing.The measurement results show that a pair of MMUX/MDEMUX and 25 km weakly-coupled TRC-FMF MDM link achieve low modal crosstalk of lower than−17.5 dB and insertion loss of lower than 11.56 dB for all the four modes.Based on the TRC-FMF and all-fiber MMUX/MDEMUX,an experiment for 25 km real-time 4-mode 3-λwavelength division multiplexing(WDM)-MDM transmission is conducted using commercial 400G optical transport network(OTN)transceivers.The experimental results prove weakly-coupled MDM techniques facilitate a smooth upgrade of the optical transmission system.展开更多
Mode-division multiplexers(MDMUXs)play a pivotal role in enabling the manipulation of an arbitrary optical state within few-mode fibers,offering extensive utility in the fields of mode-division multiplexing and struct...Mode-division multiplexers(MDMUXs)play a pivotal role in enabling the manipulation of an arbitrary optical state within few-mode fibers,offering extensive utility in the fields of mode-division multiplexing and structured optical field engineering.The exploration of MDMUXs employing cascaded resonant couplers has garnered significant attention owing to their scalability,exceptional integration capabilities,and the anticipated low insertion loss.In this work,we present the successful realization of high-quality orbital angular momentum MDMUX corresponding to topological charges 0,±1,and±2,achieved through the utilization of cascaded fused-biconical tapered couplers.Notably,the measured insertion losses at 1550 nm exhibit remarkable minimal values:0.31,0.10,and 0.64 dB,respectively.Furthermore,the 80%efficiency bandwidths exceed 106,174,and 174 nm for these respective modes.The MDMUX is composed of precisionmanufactured high-quality mode selective couplers(MSCs).Utilizing a proposed supermode propagation method based on mode composition analysis,we precisely describe the operational characteristics of MSCs.Building upon this comprehensive understanding,we embark on a pioneering analysis elucidating the influence of MSC cascading order on the performance of MDMUXs.Our theoretical investigation substantiates that when constructing MDMUXs,MSCs should adhere to a specific cascading sequence.展开更多
A multiplexer with a low-distortion high-bandwidth analog switch is presented. The gate-to-source voltage of the switch is set by the combined on-voltage of a pMOS and an nMOS,and the difference between its gate-sourc...A multiplexer with a low-distortion high-bandwidth analog switch is presented. The gate-to-source voltage of the switch is set by the combined on-voltage of a pMOS and an nMOS,and the difference between its gate-source voltage and the threshold voltage （VGST） is guaranteed to be constant with input variation. Thus, the body effect is nearly canceled. Implemented in a TSMC 0.18μm CMOS process, results from HSPICE simulation show that the VGST is nearly constant with an input range from 0.3 to 1.7V,and the - 3dB bandwidth is larger than 10GHz;the SFDR （spurious free dynamic range） of the output is 67. lldB with 1GHz input frequency; the turn-on time is 2.98ns,and the turn-off time is 1.35ns, which indicates a break-before-make action of the multiplexer. The proposed structure can be applied to high speed signal transmission.展开更多
A high-performance silicon arrayed-waveguide grating(AWG)with 0.4-nm channel spacing for dense wavelength-division multiplexing systems is designed and realized successfully.The device design involves broadening the a...A high-performance silicon arrayed-waveguide grating(AWG)with 0.4-nm channel spacing for dense wavelength-division multiplexing systems is designed and realized successfully.The device design involves broadening the arrayed waveguides far beyond the single-mode regime,which minimizes random phase errors and propagation loss without requiring any additional fabrication steps.To further enhance performance,Euler bends have been incorporated into the arrayed waveguides to reduce the device’s physical footprint and suppress the excitation of higher modes.In addition,shallowly etched transition regions are introduced at the junctions between the free-propagation regions and the arrayed waveguides to minimize mode mismatch losses.As an example,a 32×32 AWG(de)multiplexer with a compact size of 900μm×2200μm is designed and demonstrated with a narrow channel spacing of 0.4 nm by utilizing 220-nm-thick silicon photonic waveguides.The measured excess loss for the central channel is∼0.65 dB,the channel nonuniformity is around 2.5 dB,while the adjacent-channel crosstalk of the central output port is−21.4 dB.To the best of our knowledge,this AWG(de)multiplexer is the best one among silicon-based implementations currently available,offering both dense channel spacing and a large number of channels.展开更多
A 32-channel wavelength division multiplexer with 100 GHz spacing is designed and fabricated by interleaving two silicon arrayed waveguide gratings(AWGs).It has a parallel structure consisting of two silicon 16-channe...A 32-channel wavelength division multiplexer with 100 GHz spacing is designed and fabricated by interleaving two silicon arrayed waveguide gratings(AWGs).It has a parallel structure consisting of two silicon 16-channel AWGs with200 GHz spacing and a Mach-Zehnder interferometer(MZI)with 200 GHz free spectral range.The 16 channels of one silicon AWG are interleaved with those of the other AWG in spectrum,but with an identical spacing of 200 GHz.For the composed wavelength division multiplexer,the experiment results reveal 32 wavelength channels in C-band,a wavelength spacing of 100 GHz,and a channel crosstalk lower than-15 dB.展开更多
The structures of the space switching and the wavelength switching optical cross connect (OXC) nodes which are based on the arrayed waveguide grating (AWG) multiplexer are analyzed.By the matrix transformation relatio...The structures of the space switching and the wavelength switching optical cross connect (OXC) nodes which are based on the arrayed waveguide grating (AWG) multiplexer are analyzed.By the matrix transformation relation between the input and output wavelengths of the AWG multiplexer, the wavelength transmission routings of the space switching and wavelength switching OXC nodes are determined.展开更多
We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain...We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain sensor, and a 48-channel DWDM.This system can monitor temperature and strain changes at the same time.The ranges of these two sensors are from-20℃ to 100℃ and from-1000 με to 2000 με, respectively.The sensitivities of the temperature sensor and strain sensor are 0.03572 nm/℃ and 0.03808 nm/N, respectively.With the aid of a broadband source and spectrometer,different kinds and ranges of parameters in the environment can be monitored by using suitable sensors.展开更多
We have successfully demonstrated a 1 Kb spin-orbit torque(SOT)magnetic random-access memory(MRAM)multiplexer(MUX)array with remarkable performance.The 1 Kb MUX array exhibits an in-die function yield of over 99.6%.Ad...We have successfully demonstrated a 1 Kb spin-orbit torque(SOT)magnetic random-access memory(MRAM)multiplexer(MUX)array with remarkable performance.The 1 Kb MUX array exhibits an in-die function yield of over 99.6%.Additionally,it provides a sufficient readout window,with a TMR/RP_sigma%value of 21.4.Moreover,the SOT magnetic tunnel junctions(MTJs)in the array show write error rates as low as 10^(-6)without any ballooning effects or back-hopping behaviors,ensuring the write stability and reliability.This array achieves write operations in 20 ns and 1.2 V for an industrial-level temperature range from-40 to 125℃.Overall,the demonstrated array shows competitive specifications compared to the state-of-the-art works.Our work paves the way for the industrial-scale production of SOT-MRAM,moving this technology beyond R&D and towards widespread adoption.展开更多
The periodic cell stream is a very important member among the input traffic sources in ATM networks. In this paper, a finite-buffered ATM multiplexer with traffic sources composed of a periodic cell stream, multiple i...The periodic cell stream is a very important member among the input traffic sources in ATM networks. In this paper, a finite-buffered ATM multiplexer with traffic sources composed of a periodic cell stream, multiple i.i.d Bernoulli cell streams and bursty two-state Markov Modulated Bernoulli Process (MMBP) cell streams is exactly analyzed. The probability mass function of queuing delay, the autocorrelation and power spectrum of delay jitter for this periodic cell stream are derived. The analysis is used to expose the behavior of delay jitter for a periodic cell stream through an ATM multiplexer in a bursty traffic environment. The simulation results indicate that the analytical results are accurate.展开更多
Recent empirical studies of the real traffic measurement show that the traditional traffic models cannot capture the character of long-range dependence of the traffic. And many computer simulations said that this char...Recent empirical studies of the real traffic measurement show that the traditional traffic models cannot capture the character of long-range dependence of the traffic. And many computer simulations said that this character has large influences on the network performance. So fractal or self-similar models are more suitable to describe the modern traffic. But there is still little known about the performance of the multiplexer under self-similar traffic. In this paper, a quasi-self-similar traffic model (QSSP) is proposed. Using this model, the upper bond of the cell loss rate and multiplexing gain of the multiplexer are gotten when there are N i.i.d. QSSP inputs. If the sources have different parameters, an efficient numerical algorithm to get, this bond is proposed. Simulations indicate that our analysis is correct and accurate.展开更多
The operation principle of an arrayed waveguide grating(AWG) multiplexer is introduced and the 4×4 AWG with following design parameters is discussed in detail, such as the choice of wavelength, the neighboring ar...The operation principle of an arrayed waveguide grating(AWG) multiplexer is introduced and the 4×4 AWG with following design parameters is discussed in detail, such as the choice of wavelength, the neighboring arrayed waveguide distance ΔL, the channel frequency interval Δf, and the free spectral range. The structure of 4×4 AWG is designed and the result of stimulated test is also given. Analysis shows that the 4×4 AWG is characterized by a wide dynamic range, low crosstalk, better spectrum properties, and a compact structure.展开更多
A plastic surface-relief grating as a wavelength division multiplexer is designed and fabricated with the conventional mould pressing technique using the transmission-type fused quartz phase grating as mask pattern an...A plastic surface-relief grating as a wavelength division multiplexer is designed and fabricated with the conventional mould pressing technique using the transmission-type fused quartz phase grating as mask pattern and polycarbonate as basal material.The experiment results show that in an optimizing process,the plastic surface-relief grating has the highest firstorder diffraction efficiency under adequate groove depth and incident angle,and can be used as the best optical path for wavelength division multiplexing(WDM).We also establish the experiment setup for testing the WDM performance of the plastic surface-relief grating based wavelength division multiplexer.The results show that the proposed wavelength division multiplexer has the high-stability temperature characteristics,the low insertion loss of less than 5 dB,the large isolation of greater than 20 dB,the low polarization-dependent loss(PDL) of less than 0.4 dB and the relatively steep pass-band characteristics.It is a WDM device with good performance,which can be applied in short distance communication.展开更多
A cross-linkable fluorinated poly (ether ether ketone) (FPEEK) was synthesized for the fabrication of arrayed waveguide grating (AWG) multiplexer. The results of thermal gravimetric analysis (TGA) and near-infrared ab...A cross-linkable fluorinated poly (ether ether ketone) (FPEEK) was synthesized for the fabrication of arrayed waveguide grating (AWG) multiplexer. The results of thermal gravimetric analysis (TGA) and near-infrared absorption spectrum show that the materials have high thermal stability and high optical transparency in the infrared communication region. The refractive index of FPEEK can be controlled easily by changing the fluorine content of the materials. The 32-channel AWG multiplexer is fabricated using the FPEEK and oxygen reactive ion etching technology. The AWG multiplexer exhibits that the insertion loss is from 12.8 to 17.8 dB and the channel crosstalk is less than-20 dB. The wavelength channel spacing and the center wavelength are 0.8nm and 1548nm, respectively.展开更多
<div style="text-align:justify;"> We present a mode converter and demultiplexer structure for wavelength division multiplexing (WDM) transmission by employing multimode interference (MMI) on Silicon-on...<div style="text-align:justify;"> We present a mode converter and demultiplexer structure for wavelength division multiplexing (WDM) transmission by employing multimode interference (MMI) on Silicon-on-Insulator (SOI) platform. The mode converter and demultiplexer have a compact size of less than 2.7 μm × 43.7 μm. Moreover, the crosstalk between neighboring wavelength channel within C band (1530 nm to 1570 nm) can be reduced by utilizing the tapered phase shifter cascaded with MMI. The simulated results indicate that this structure has a low insertion loss of less than 1 dB, a low crosstalk of better than ?15 dB and a relatively high fabrication tolerance of ~10 nm. Such structure may find many potential applications in silicon photonic integrated devices. </div>展开更多
Dealing with the increase in data workloads and network complexity requires efficient selective manipulation of any channels in hybrid mode-/wavelength-division multiplexing(MDM/WDM)systems.A reconfigurable optical ad...Dealing with the increase in data workloads and network complexity requires efficient selective manipulation of any channels in hybrid mode-/wavelength-division multiplexing(MDM/WDM)systems.A reconfigurable optical add-drop multiplexer(ROADM)using special modal field redistribution is proposed and demonstrated to enable the selective access of any mode-/wavelength-channels.With the assistance of the subwavelength grating structures,the launched modes are redistributed to be the supermodes localized at different regions of the multimode bus waveguide.Microring resonators are placed at the corresponding side of the bus waveguide to have specific evanescent coupling of the redistributed supermodes,so that any mode-/wavelength-channel can be added/dropped by thermally tuning the resonant wavelength.As an example,a ROADM for the case with three mode-channels is designed with low excess losses of<0.6,0.7,and 1.3 dB as well as low cross talks of<−26.3,−28.5,and−39.3 dB for the TE0,TE1,and TE2 modes,respectively,around the central wavelength of 1550 nm.The data transmission of 30 Gbps∕channel is also demonstrated successfully.The present ROADM provides a promising route for data switching/routing in hybrid MDM/WDM systems.展开更多
We present the design, fabrication, and characterization of a dual polarization, mode-selective photonic lantern(PL) spatial multiplexer supporting three fiber modes (LP_(01), LP^(a)_(11), LP^(b)_(11)), measuring only...We present the design, fabrication, and characterization of a dual polarization, mode-selective photonic lantern(PL) spatial multiplexer supporting three fiber modes (LP_(01), LP^(a)_(11), LP^(b)_(11)), measuring only 300μm in length, for converting between three single-mode input sources and a single three-mode optical fiber. The PL is fabricated directly on the three sources, in this case three cores of a multi-core fiber, using a commercial two-photon polymerization-based 3D nanoprinter. Despite the diminutive size and high index contrast of the polymer core/air cladding waveguides, we observed low insertion loss multiplexing (less than-1.7 d B), low polarization dependent loss (less than-0.25 dB), mode dependent loss of-1.7 d B, low wavelength dependence, and mode group crosstalk of less than-16 dB. We demonstrate mode group multiplexed transmission using our mode-selective multiplexer/demultiplexer pair and a short three-mode fiber link in an on-off keying intensity modulation/direct detection(IM/DD) experiment, recovering two 12.5 Gb/s signals without MIMO processing.展开更多
Femtosecond laser fabrication technology has been applied to photonic-lantern mode(de)multiplexers owing to its 3D fabrication capability.Current photonic-lantern mode(de)multiplexer designs based on femtosecond laser...Femtosecond laser fabrication technology has been applied to photonic-lantern mode(de)multiplexers owing to its 3D fabrication capability.Current photonic-lantern mode(de)multiplexer designs based on femtosecond laser fabrication technology mostly follow a fibre-type photonic lantern design,which uses trajectory-symmetry structures with non-uniform waveguides for selective mode excitation.However,non-uniform waveguides can lead to inconsistent waveguide transmission and coupling losses.Trajectory-symmetry designs are inefficient for selective-mode excitation.Therefore,we optimised the design using trajectory asymmetry with uniform waveguides and fabricated superior ultrafast laser-inscribed photonic-lantern mode(de)multiplexers.Consistent waveguide transmission and coupling losses(0.1 dB/cm and 0.2 dB/facet,respectively)at 1550 nm were obtained on uniform single-mode waveguides.Based on the trajectory-asymmetry design for photonic-lantern mode LPa11 LPb11 LP01(de)multiplexers,efficient mode excitation(,,and)with average insertion losses as low as 1 dB at 1550 nm was achieved,with mode-dependent losses of less than 0.3 dB.The photonic-lantern design was polarisation-insensitive,and the polarisation-determined losses were less than 0.2 dB.Along with polarisation LPa11x LPa11y LPb11x LPb11y LP01xmultiplexing realised by fibre-type polarisation beam splitters,six signal channels(,,,,,LP01yand),each carrying 42 Gaud/s quadrature phase-shift keying signals,were transmitted through a few-mode fibre for optical transmission.The average insertion loss of the system is less than 5 dB,while its maximum crosstalk with the few-mode fibre is less than-12 dB,leading to a 4-dB power penalty.The findings of this study pave the way for the practical application of 3D integrated photonic chips in high-capacity optical transmission systems.展开更多
On-chip multidimensional multiplexing has shown considerable potential for enhancing transmission capacity and developing communication networks in integrated optical systems.Micro-ring resonators,which utilize the wa...On-chip multidimensional multiplexing has shown considerable potential for enhancing transmission capacity and developing communication networks in integrated optical systems.Micro-ring resonators,which utilize the wavelength-dependent whispering gallery resonance mechanism and feature customizable cavity lengths,offer inherent advantages for accurate wavelength filtering.These characteristics make them promising candidates for wavelength multiplexers.However,a significant challenge arises from the mismatch in the effective refractive index between orthogonal linear polarizations,which introduces complexities to polarization channel multiplexing and impedes progress in on-chip multidimensional multiplexing that integrates both wavelength and polarization channels.In this work,we propose a double-layer adiabatic structureconnected micro-ring resonator(AMRR)with vertical refractive index asymmetry,demonstrating its utility in multidimensional(de)multiplexers.Our approach enables polarization division multiplexing(PDM)by facilitating polarization rotation between transverse electric and transverse magnetic polarizations through polarization hybridization.The(de)multiplexing of both wavelength and polarization channels is achieved by controlling the incident light direction and filtering the resonance wavelength within the micro-ring resonator.As a proof of concept,we successfully transmitted 144 Gbit/s QPSK-OFDM signals and achieved bit error rates below the forward error correction threshold at-19 d Bm using the proposed multidimensional(de)multiplexer,which accommodates 3 wavelengths and 2 polarizations.Our design,which leverages the AMRR for simultaneous(de)multiplexing of wavelength and polarization channels,not only overcomes the limitation of traditional micro-ring resonators in implementing PDM,but also reduces the footprint of the multidimensional(de)multiplexer to 27μm×219μm,an order of magnitude smaller compared to conventional designs.展开更多
This paper proves that a synchronous demultiplexer has the same logic function as a synchronous multiplexer. A new approach is proposed to implement synchronous demultiplexers in high-speed ISDN switching networks. A ...This paper proves that a synchronous demultiplexer has the same logic function as a synchronous multiplexer. A new approach is proposed to implement synchronous demultiplexers in high-speed ISDN switching networks. A synchronous demultiplexer is designed utilizing the same structure as a synchronous shuffle multiplexer. Both the theoretical analysis and experimental results show that for the same capacity, the new method is more tolerant of signal delay variation, so a very high-speed synchronous demultiplexer can be designed with the larger capacity required in large capacity synchronous switching networks.展开更多
A decomposition approach of the combinational functions is discussed. A design method, by which the minimization or near minimization of two-level combinational network can be obtained, is presented for a combinationa...A decomposition approach of the combinational functions is discussed. A design method, by which the minimization or near minimization of two-level combinational network can be obtained, is presented for a combinational function realized by using multiplexer universal logic modules. Using the method, the automated synthesis of the combinational functions can be accomplished on a computer.展开更多
基金supported in part by the ZTE Industry-University-Institute Cooperation Funds.
文摘Weakly-coupled mode division multiplexing(MDM)technique is considered a promising candidate to enhance the capacity of an optical transmission system,in which mode multiplexers/demultiplexers(MMUX/MDEMUX)with low insertion loss and modal crosstalk are the key components.In this paper,a low-modal-crosstalk 4-mode MMUX/MDEMUX for the weakly-coupled triple-ring-core few-mode fiber(TRC-FMF)is designed and fabricated with side-polishing processing.The measurement results show that a pair of MMUX/MDEMUX and 25 km weakly-coupled TRC-FMF MDM link achieve low modal crosstalk of lower than−17.5 dB and insertion loss of lower than 11.56 dB for all the four modes.Based on the TRC-FMF and all-fiber MMUX/MDEMUX,an experiment for 25 km real-time 4-mode 3-λwavelength division multiplexing(WDM)-MDM transmission is conducted using commercial 400G optical transport network(OTN)transceivers.The experimental results prove weakly-coupled MDM techniques facilitate a smooth upgrade of the optical transmission system.
基金supported by the National Key Research and Development Program of China (Grant No.2018YFB1801802)the National Natural Science Foundation of China (Grant Nos.62375143 and 61835006).
文摘Mode-division multiplexers(MDMUXs)play a pivotal role in enabling the manipulation of an arbitrary optical state within few-mode fibers,offering extensive utility in the fields of mode-division multiplexing and structured optical field engineering.The exploration of MDMUXs employing cascaded resonant couplers has garnered significant attention owing to their scalability,exceptional integration capabilities,and the anticipated low insertion loss.In this work,we present the successful realization of high-quality orbital angular momentum MDMUX corresponding to topological charges 0,±1,and±2,achieved through the utilization of cascaded fused-biconical tapered couplers.Notably,the measured insertion losses at 1550 nm exhibit remarkable minimal values:0.31,0.10,and 0.64 dB,respectively.Furthermore,the 80%efficiency bandwidths exceed 106,174,and 174 nm for these respective modes.The MDMUX is composed of precisionmanufactured high-quality mode selective couplers(MSCs).Utilizing a proposed supermode propagation method based on mode composition analysis,we precisely describe the operational characteristics of MSCs.Building upon this comprehensive understanding,we embark on a pioneering analysis elucidating the influence of MSC cascading order on the performance of MDMUXs.Our theoretical investigation substantiates that when constructing MDMUXs,MSCs should adhere to a specific cascading sequence.
文摘A multiplexer with a low-distortion high-bandwidth analog switch is presented. The gate-to-source voltage of the switch is set by the combined on-voltage of a pMOS and an nMOS,and the difference between its gate-source voltage and the threshold voltage （VGST） is guaranteed to be constant with input variation. Thus, the body effect is nearly canceled. Implemented in a TSMC 0.18μm CMOS process, results from HSPICE simulation show that the VGST is nearly constant with an input range from 0.3 to 1.7V,and the - 3dB bandwidth is larger than 10GHz;the SFDR （spurious free dynamic range） of the output is 67. lldB with 1GHz input frequency; the turn-on time is 2.98ns,and the turn-off time is 1.35ns, which indicates a break-before-make action of the multiplexer. The proposed structure can be applied to high speed signal transmission.
基金supported by the National Natural Science Foundation of China(Grant Nos.U23B2047,62321166651,62205292,and 92150302)the Zhejiang Major Research and Development Program(Grant No.2021C01199)+1 种基金the Zhejiang Provincial Natural Science Foundation(Grant Nos.LZ18F050001,LD19F050001,LQ21F050006,and LD22F040004)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(Grant No.2021R01001)。
文摘A high-performance silicon arrayed-waveguide grating(AWG)with 0.4-nm channel spacing for dense wavelength-division multiplexing systems is designed and realized successfully.The device design involves broadening the arrayed waveguides far beyond the single-mode regime,which minimizes random phase errors and propagation loss without requiring any additional fabrication steps.To further enhance performance,Euler bends have been incorporated into the arrayed waveguides to reduce the device’s physical footprint and suppress the excitation of higher modes.In addition,shallowly etched transition regions are introduced at the junctions between the free-propagation regions and the arrayed waveguides to minimize mode mismatch losses.As an example,a 32×32 AWG(de)multiplexer with a compact size of 900μm×2200μm is designed and demonstrated with a narrow channel spacing of 0.4 nm by utilizing 220-nm-thick silicon photonic waveguides.The measured excess loss for the central channel is∼0.65 dB,the channel nonuniformity is around 2.5 dB,while the adjacent-channel crosstalk of the central output port is−21.4 dB.To the best of our knowledge,this AWG(de)multiplexer is the best one among silicon-based implementations currently available,offering both dense channel spacing and a large number of channels.
基金Project supported by the National Key Research and Development Program of China(Grant No.2019YFB2203600)。
文摘A 32-channel wavelength division multiplexer with 100 GHz spacing is designed and fabricated by interleaving two silicon arrayed waveguide gratings(AWGs).It has a parallel structure consisting of two silicon 16-channel AWGs with200 GHz spacing and a Mach-Zehnder interferometer(MZI)with 200 GHz free spectral range.The 16 channels of one silicon AWG are interleaved with those of the other AWG in spectrum,but with an identical spacing of 200 GHz.For the composed wavelength division multiplexer,the experiment results reveal 32 wavelength channels in C-band,a wavelength spacing of 100 GHz,and a channel crosstalk lower than-15 dB.
基金NationalKeyLabofBroadBandFiberTransmissionandCommunicatonSystemTechnology ElectronicUniversityofScienceandTechnology China
文摘The structures of the space switching and the wavelength switching optical cross connect (OXC) nodes which are based on the arrayed waveguide grating (AWG) multiplexer are analyzed.By the matrix transformation relation between the input and output wavelengths of the AWG multiplexer, the wavelength transmission routings of the space switching and wavelength switching OXC nodes are determined.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0402504)the National Natural Science Foundation of China(Grant Nos.61875069 and 61575076)+1 种基金Hong Kong Scholars Program,China(Grant No.XJ2016026)the Science and Technology Development Plan of Jilin Province,China(Grant Nos.20190302010GX and 20160520091JH)
文摘We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain sensor, and a 48-channel DWDM.This system can monitor temperature and strain changes at the same time.The ranges of these two sensors are from-20℃ to 100℃ and from-1000 με to 2000 με, respectively.The sensitivities of the temperature sensor and strain sensor are 0.03572 nm/℃ and 0.03808 nm/N, respectively.With the aid of a broadband source and spectrometer,different kinds and ranges of parameters in the environment can be monitored by using suitable sensors.
基金supported by the National Key Research and Development Program of China (Nos.2021YFB3601303,2021YFB3601304,2021YFB3601300,2022YFB4400200,2022YFB4400201,2022YFB4400203)the National Natural Science Foundation of China (Grant No.62171013)。
文摘We have successfully demonstrated a 1 Kb spin-orbit torque(SOT)magnetic random-access memory(MRAM)multiplexer(MUX)array with remarkable performance.The 1 Kb MUX array exhibits an in-die function yield of over 99.6%.Additionally,it provides a sufficient readout window,with a TMR/RP_sigma%value of 21.4.Moreover,the SOT magnetic tunnel junctions(MTJs)in the array show write error rates as low as 10^(-6)without any ballooning effects or back-hopping behaviors,ensuring the write stability and reliability.This array achieves write operations in 20 ns and 1.2 V for an industrial-level temperature range from-40 to 125℃.Overall,the demonstrated array shows competitive specifications compared to the state-of-the-art works.Our work paves the way for the industrial-scale production of SOT-MRAM,moving this technology beyond R&D and towards widespread adoption.
文摘The periodic cell stream is a very important member among the input traffic sources in ATM networks. In this paper, a finite-buffered ATM multiplexer with traffic sources composed of a periodic cell stream, multiple i.i.d Bernoulli cell streams and bursty two-state Markov Modulated Bernoulli Process (MMBP) cell streams is exactly analyzed. The probability mass function of queuing delay, the autocorrelation and power spectrum of delay jitter for this periodic cell stream are derived. The analysis is used to expose the behavior of delay jitter for a periodic cell stream through an ATM multiplexer in a bursty traffic environment. The simulation results indicate that the analytical results are accurate.
文摘Recent empirical studies of the real traffic measurement show that the traditional traffic models cannot capture the character of long-range dependence of the traffic. And many computer simulations said that this character has large influences on the network performance. So fractal or self-similar models are more suitable to describe the modern traffic. But there is still little known about the performance of the multiplexer under self-similar traffic. In this paper, a quasi-self-similar traffic model (QSSP) is proposed. Using this model, the upper bond of the cell loss rate and multiplexing gain of the multiplexer are gotten when there are N i.i.d. QSSP inputs. If the sources have different parameters, an efficient numerical algorithm to get, this bond is proposed. Simulations indicate that our analysis is correct and accurate.
文摘The operation principle of an arrayed waveguide grating(AWG) multiplexer is introduced and the 4×4 AWG with following design parameters is discussed in detail, such as the choice of wavelength, the neighboring arrayed waveguide distance ΔL, the channel frequency interval Δf, and the free spectral range. The structure of 4×4 AWG is designed and the result of stimulated test is also given. Analysis shows that the 4×4 AWG is characterized by a wide dynamic range, low crosstalk, better spectrum properties, and a compact structure.
基金supported by the Natural Science Foundation of Fujian Province of China (No.2011J01353)
文摘A plastic surface-relief grating as a wavelength division multiplexer is designed and fabricated with the conventional mould pressing technique using the transmission-type fused quartz phase grating as mask pattern and polycarbonate as basal material.The experiment results show that in an optimizing process,the plastic surface-relief grating has the highest firstorder diffraction efficiency under adequate groove depth and incident angle,and can be used as the best optical path for wavelength division multiplexing(WDM).We also establish the experiment setup for testing the WDM performance of the plastic surface-relief grating based wavelength division multiplexer.The results show that the proposed wavelength division multiplexer has the high-stability temperature characteristics,the low insertion loss of less than 5 dB,the large isolation of greater than 20 dB,the low polarization-dependent loss(PDL) of less than 0.4 dB and the relatively steep pass-band characteristics.It is a WDM device with good performance,which can be applied in short distance communication.
文摘A cross-linkable fluorinated poly (ether ether ketone) (FPEEK) was synthesized for the fabrication of arrayed waveguide grating (AWG) multiplexer. The results of thermal gravimetric analysis (TGA) and near-infrared absorption spectrum show that the materials have high thermal stability and high optical transparency in the infrared communication region. The refractive index of FPEEK can be controlled easily by changing the fluorine content of the materials. The 32-channel AWG multiplexer is fabricated using the FPEEK and oxygen reactive ion etching technology. The AWG multiplexer exhibits that the insertion loss is from 12.8 to 17.8 dB and the channel crosstalk is less than-20 dB. The wavelength channel spacing and the center wavelength are 0.8nm and 1548nm, respectively.
文摘<div style="text-align:justify;"> We present a mode converter and demultiplexer structure for wavelength division multiplexing (WDM) transmission by employing multimode interference (MMI) on Silicon-on-Insulator (SOI) platform. The mode converter and demultiplexer have a compact size of less than 2.7 μm × 43.7 μm. Moreover, the crosstalk between neighboring wavelength channel within C band (1530 nm to 1570 nm) can be reduced by utilizing the tapered phase shifter cascaded with MMI. The simulated results indicate that this structure has a low insertion loss of less than 1 dB, a low crosstalk of better than ?15 dB and a relatively high fabrication tolerance of ~10 nm. Such structure may find many potential applications in silicon photonic integrated devices. </div>
基金supported by the National Major Research and Development Program(Grant No.2019YFB2203600)the National Science Fund for Distinguished Young Scholars(Grant No.61725503)+3 种基金the National Natural Science Foundation of China(Grant Nos.62125503,91950205,61961146003,and 62005238)the Zhejiang Provincial Natural Science Foundation(Grant No.LD19F050001)The Fundamental Research Funds for the Central UniversitiesThe Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(Grant No.2021R01001).
文摘Dealing with the increase in data workloads and network complexity requires efficient selective manipulation of any channels in hybrid mode-/wavelength-division multiplexing(MDM/WDM)systems.A reconfigurable optical add-drop multiplexer(ROADM)using special modal field redistribution is proposed and demonstrated to enable the selective access of any mode-/wavelength-channels.With the assistance of the subwavelength grating structures,the launched modes are redistributed to be the supermodes localized at different regions of the multimode bus waveguide.Microring resonators are placed at the corresponding side of the bus waveguide to have specific evanescent coupling of the redistributed supermodes,so that any mode-/wavelength-channel can be added/dropped by thermally tuning the resonant wavelength.As an example,a ROADM for the case with three mode-channels is designed with low excess losses of<0.6,0.7,and 1.3 dB as well as low cross talks of<−26.3,−28.5,and−39.3 dB for the TE0,TE1,and TE2 modes,respectively,around the central wavelength of 1550 nm.The data transmission of 30 Gbps∕channel is also demonstrated successfully.The present ROADM provides a promising route for data switching/routing in hybrid MDM/WDM systems.
文摘We present the design, fabrication, and characterization of a dual polarization, mode-selective photonic lantern(PL) spatial multiplexer supporting three fiber modes (LP_(01), LP^(a)_(11), LP^(b)_(11)), measuring only 300μm in length, for converting between three single-mode input sources and a single three-mode optical fiber. The PL is fabricated directly on the three sources, in this case three cores of a multi-core fiber, using a commercial two-photon polymerization-based 3D nanoprinter. Despite the diminutive size and high index contrast of the polymer core/air cladding waveguides, we observed low insertion loss multiplexing (less than-1.7 d B), low polarization dependent loss (less than-0.25 dB), mode dependent loss of-1.7 d B, low wavelength dependence, and mode group crosstalk of less than-16 dB. We demonstrate mode group multiplexed transmission using our mode-selective multiplexer/demultiplexer pair and a short three-mode fiber link in an on-off keying intensity modulation/direct detection(IM/DD) experiment, recovering two 12.5 Gb/s signals without MIMO processing.
基金supported by the National Natural Science Foundation of China(NSFC)(62125503,62261160388)the Natural Science Foundation of Hubei Province of China(2023AFA028)the Innovation Project of Optics Valley Laboratory(OVL2021BG004).
文摘Femtosecond laser fabrication technology has been applied to photonic-lantern mode(de)multiplexers owing to its 3D fabrication capability.Current photonic-lantern mode(de)multiplexer designs based on femtosecond laser fabrication technology mostly follow a fibre-type photonic lantern design,which uses trajectory-symmetry structures with non-uniform waveguides for selective mode excitation.However,non-uniform waveguides can lead to inconsistent waveguide transmission and coupling losses.Trajectory-symmetry designs are inefficient for selective-mode excitation.Therefore,we optimised the design using trajectory asymmetry with uniform waveguides and fabricated superior ultrafast laser-inscribed photonic-lantern mode(de)multiplexers.Consistent waveguide transmission and coupling losses(0.1 dB/cm and 0.2 dB/facet,respectively)at 1550 nm were obtained on uniform single-mode waveguides.Based on the trajectory-asymmetry design for photonic-lantern mode LPa11 LPb11 LP01(de)multiplexers,efficient mode excitation(,,and)with average insertion losses as low as 1 dB at 1550 nm was achieved,with mode-dependent losses of less than 0.3 dB.The photonic-lantern design was polarisation-insensitive,and the polarisation-determined losses were less than 0.2 dB.Along with polarisation LPa11x LPa11y LPb11x LPb11y LP01xmultiplexing realised by fibre-type polarisation beam splitters,six signal channels(,,,,,LP01yand),each carrying 42 Gaud/s quadrature phase-shift keying signals,were transmitted through a few-mode fibre for optical transmission.The average insertion loss of the system is less than 5 dB,while its maximum crosstalk with the few-mode fibre is less than-12 dB,leading to a 4-dB power penalty.The findings of this study pave the way for the practical application of 3D integrated photonic chips in high-capacity optical transmission systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.62271322,62331004,and 62222501)Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515030152)+5 种基金the Science and Technology Project of Shenzhen(Grant No.ZDSYS201707271014468)Shenzhen Science and Technology Program(Grant No.JCYJ20240813143018024)the Natural Science Foundation of Top Talent of SZTU(Grant No.GDRC202204)Qianxinan Prefecture Science and Technology Plan Project(Grant No.2023123)the Scientific Research Fund Project of Minzu Normal University of Xingyi(Grant No.23XYZD07)Guizhou Province Youth Science and Technology Talent Development Project(Qian Jiaoji[2024]No.244)。
文摘On-chip multidimensional multiplexing has shown considerable potential for enhancing transmission capacity and developing communication networks in integrated optical systems.Micro-ring resonators,which utilize the wavelength-dependent whispering gallery resonance mechanism and feature customizable cavity lengths,offer inherent advantages for accurate wavelength filtering.These characteristics make them promising candidates for wavelength multiplexers.However,a significant challenge arises from the mismatch in the effective refractive index between orthogonal linear polarizations,which introduces complexities to polarization channel multiplexing and impedes progress in on-chip multidimensional multiplexing that integrates both wavelength and polarization channels.In this work,we propose a double-layer adiabatic structureconnected micro-ring resonator(AMRR)with vertical refractive index asymmetry,demonstrating its utility in multidimensional(de)multiplexers.Our approach enables polarization division multiplexing(PDM)by facilitating polarization rotation between transverse electric and transverse magnetic polarizations through polarization hybridization.The(de)multiplexing of both wavelength and polarization channels is achieved by controlling the incident light direction and filtering the resonance wavelength within the micro-ring resonator.As a proof of concept,we successfully transmitted 144 Gbit/s QPSK-OFDM signals and achieved bit error rates below the forward error correction threshold at-19 d Bm using the proposed multidimensional(de)multiplexer,which accommodates 3 wavelengths and 2 polarizations.Our design,which leverages the AMRR for simultaneous(de)multiplexing of wavelength and polarization channels,not only overcomes the limitation of traditional micro-ring resonators in implementing PDM,but also reduces the footprint of the multidimensional(de)multiplexer to 27μm×219μm,an order of magnitude smaller compared to conventional designs.
文摘This paper proves that a synchronous demultiplexer has the same logic function as a synchronous multiplexer. A new approach is proposed to implement synchronous demultiplexers in high-speed ISDN switching networks. A synchronous demultiplexer is designed utilizing the same structure as a synchronous shuffle multiplexer. Both the theoretical analysis and experimental results show that for the same capacity, the new method is more tolerant of signal delay variation, so a very high-speed synchronous demultiplexer can be designed with the larger capacity required in large capacity synchronous switching networks.
文摘A decomposition approach of the combinational functions is discussed. A design method, by which the minimization or near minimization of two-level combinational network can be obtained, is presented for a combinational function realized by using multiplexer universal logic modules. Using the method, the automated synthesis of the combinational functions can be accomplished on a computer.
