Miniaturized spectrometers have been widely researched in recent years,but few studies are conducted with on-chip multimode schemes for mode-division multiplexing(MDM)systems.Here we propose an ultracompact mode-divis...Miniaturized spectrometers have been widely researched in recent years,but few studies are conducted with on-chip multimode schemes for mode-division multiplexing(MDM)systems.Here we propose an ultracompact mode-division demultiplexing spectrometer that includes branched waveguide structures and graphene-based photodetectors,which realizes simultaneously spectral dispersing and light fields detecting.In the bandwidth of 1500-1600 nm,the designed spectrometer achieves the single-mode spectral resolution of 7 nm for each mode of TE_(1)-TE_(4) by Tikhonov regularization optimization.Empowered by deep learning algorithms,the 15-nm resolution of parallel reconstruction for TE_(1)-TE_(4) is achieved by a single-shot measurement.Moreover,by stacking the multimode response in TE_(1)-TE_(4) to the single spectra,the 3-nm spectral resolution is realized.This design reveals an effective solution for on-chip MDM spectroscopy,and may find applications in multimode sensing,interconnecting and processing.展开更多
We propose a mode demultiplexing hybrid(MDH) that integrates mode demultiplexing, local oscillator power splitting, and optical 90-deg mixing using multi-plane light conversion(MPLC). We demonstrate the realization of...We propose a mode demultiplexing hybrid(MDH) that integrates mode demultiplexing, local oscillator power splitting, and optical 90-deg mixing using multi-plane light conversion(MPLC). We demonstrate the realization of a three-mode MDH using four phase plates, one more than what is required for an MPLC-based mode demultiplexer, via numerical simulations. The performance of the three-mode MDH is comparable to that of commercial single-mode 90-deg hybrids. This multiple-functionality device enables simplification of the coherent optical front end of mode-division multiplexing receivers.展开更多
The demultiplexing experiment from a 40 Gb/s optical time-division multiplexing signal is completed by using electro- absorption sampling window based on electronic phase-locked loop circuit for clock recovery. Error-...The demultiplexing experiment from a 40 Gb/s optical time-division multiplexing signal is completed by using electro- absorption sampling window based on electronic phase-locked loop circuit for clock recovery. Error-free demultiplexing is achieved when the launched optical power into electro-absorption sampling window reaches 5.5 dBm without optical filter following the EDFA.展开更多
An 8×2.5Gb/s 100km optical time division multiplexing(OTDM) experiment system is reported, which employs an electrical filter with high Q value for clock extraction, a nonlinear optical loop mirror(NOLM) for demu...An 8×2.5Gb/s 100km optical time division multiplexing(OTDM) experiment system is reported, which employs an electrical filter with high Q value for clock extraction, a nonlinear optical loop mirror(NOLM) for demultiplering and chirped fiber grating for dispersion compensation. The error free operation is achieved and the experiment results are given.展开更多
We in this paper propose a model to increase the diffraction efficiency of a holographic grating at 1550 nm for multiplexing application. To use such a grating, polarization dependence loss is introduced analytically ...We in this paper propose a model to increase the diffraction efficiency of a holographic grating at 1550 nm for multiplexing application. To use such a grating, polarization dependence loss is introduced analytically and then optimized for its minimum value A configuration of holographic grating is proposed based on both maximum diffraction efficiency and minimum polarization dependence loss. The proposed grating is expected to find importance in optoelectronic multichip module.展开更多
A compact and fabrication friendly polarization demultiplexer(P-DEMUX) is proposed and characterized to enable wavelength-division-multiplexing and polarization-division-multiplexing simultaneously. The proposed struc...A compact and fabrication friendly polarization demultiplexer(P-DEMUX) is proposed and characterized to enable wavelength-division-multiplexing and polarization-division-multiplexing simultaneously. The proposed structure is composed of a polarization-selective microring resonator in ultrathin waveguide and two bus channels in the silicon nitridesilica-silicon horizontal slot waveguides. In the slot waveguide, the transverse electric(TE) mode propagates through the silicon layer, while the transverse magnetic(TM) mode is confined in the slot region. In the designed ultra-thin waveguide, the TM mode is cut-off. The effective indexes of the TE modes for ultrathin and slot waveguides have comparable values. Thanks for these distinguishing features, the input TE mode can be efficiently filtered through the ultra-thin microring at the resonant wavelength, while the TM mode can directly output from the through port. Simulation results show that the extinction ratio of the proposed P-DEMUX for TE and TM modes are 33.21 dB and 24.97 dB, and the insertion losses are 0.346 dB and 0.324 dB, respectively, at the wavelength of 1551.64 nm. Furthermore, the device shows a broad bandwidth(> 100 nm) for an extinction ratio(ER) of > 20 dB. In addition, the proposed P-DEMUX also has a good fabrication tolerance for the waveguide width variation of-20 nm≤ △w_(g)≤ 20 nm and the microring width variation of -20 nm≤ △w_(r) ≤20 nm for a low insertion loss of < 0.75 dB and low ER of <-18 dB.展开更多
We propose the concept of thermal demultiplexer, which can split the heat flux in different frequency ranges intodifferent directions. We demonstrate this device concept in a honeycomb lattice with dangling atoms. Fro...We propose the concept of thermal demultiplexer, which can split the heat flux in different frequency ranges intodifferent directions. We demonstrate this device concept in a honeycomb lattice with dangling atoms. From the view ofeffective negative mass, we give a qualitative explanation of how the dangling atoms change the original transport property.We first design a two-mass configuration thermal demultiplexer, and find that the heat flux can flow into different ports incorresponding frequency ranges roughly. Then, to improve the performance, we choose the suitable masses of danglingatoms and optimize the four-mass configuration with genetic algorithm. Finally, we give out the optimal configuration witha remarkable effect. Our study finds a way to selectively split spectrum-resolved heat to different ports as phonon splitter,which would provide a new means to manipulate phonons and heat, and to guide the design of phononic thermal devices inthe future.展开更多
We investigate the electronic transport in a simple mesoscopic cross structure made of two wires(stubs)grafted at the same point along a quantum waveguide.We show that the structure may exhibit important phenomena suc...We investigate the electronic transport in a simple mesoscopic cross structure made of two wires(stubs)grafted at the same point along a quantum waveguide.We show that the structure may exhibit important phenomena such as bound in continuum(BIC)states.These states are transformed into electromagnetically induced transparency(EIT)resonance by detuning slightly the lengths of the stubs.The last phenomenon is used to propose and study a mesoscopic demultiplexer device with an input waveguide and two output waveguides.We give closed-form expressions of the geometrical parameters that allow a selective transfer of a given state in the first waveguide without perturbing the second waveguide.The effect of temperature on the transmission resonances is also examined by using Landauer-Büttiker formula.The analytical results of the dispersion relation and transmission and reflection coefficient are obtained using the Green's function method.展开更多
Fiber optic Mach Zehnder interferometer(MZI) can be used as wavelength multiplexers and demultiplexers. The △ L and △ directly influence the properties of MZI. To lengthen the △ L can demultiplex much more wavelen...Fiber optic Mach Zehnder interferometer(MZI) can be used as wavelength multiplexers and demultiplexers. The △ L and △ directly influence the properties of MZI. To lengthen the △ L can demultiplex much more wavelengths, but when the △ L is longer, the temperature will influence MZI more seriously. A method to solve this problem is proposed, which enables MZI to work stably. The wavelength distance is 0.8 nm, and the extinction ratio is high.展开更多
In many domains of science and technology, as the need for secured transmission of information has grown over the years, a variety of methods have been studied and devised to achieve this goal. In this paper, we prese...In many domains of science and technology, as the need for secured transmission of information has grown over the years, a variety of methods have been studied and devised to achieve this goal. In this paper, we present an information securing method using chaos encryption. Our proposal uses only one chaotic oscillator both for signal encryption and decryption for?avoiding the delicate synchronisation step. We carried out numerical and electronic simulations of the proposed circuit using electrocardiographic signals as input. Results obtained from both simulations were compared and exhibited a good agreement proving the suitability of our system for signal encryption and decryption.展开更多
Using Terahertz Optical Asymmetric Demultiplexer (TOAD) based switch we have designed all-optical parallel half adder and full adder. The approach to design this all-optical arithmetic circuit not only enhances the co...Using Terahertz Optical Asymmetric Demultiplexer (TOAD) based switch we have designed all-optical parallel half adder and full adder. The approach to design this all-optical arithmetic circuit not only enhances the computational speed but also is capable of synthesizing light as input to produce desire output. The main advantage of parallel circuit is synchronization of input which is not required. All the circuits are designed theoretically and verified through numerical simulations.展开更多
An all-optical 3:8 decoder unit with the help of terahertz optical asymmetric demultiplexer (TOAD) is proposed. The all-optical 3:8 decoder unit with a set of all-optical full-adders and optical exclusive-ORs (XORs), ...An all-optical 3:8 decoder unit with the help of terahertz optical asymmetric demultiplexer (TOAD) is proposed. The all-optical 3:8 decoder unit with a set of all-optical full-adders and optical exclusive-ORs (XORs), can be used to perform a fast central processor unit using optical hardware components. We try to exploit the advantages of TOAD-based optical switch to design an integrated all-optical circuit which can perform decoding of signal. A theoretical model is presented and verified through numerical simulation. The new method promises both higher processing speed and accuracy. The model can be extended for studying more complex all-optical circuit of enhanced functionality in which decoder is the basic building block. The operation of the proposed circuit is parallel in nature. The impact of the switching energy with small signal gain and variation of extinction ratio and contrast ration with control pulse energy of the switching outcome is explored and assessed by means of numerical simulations.展开更多
An all-optical 2-to-4 decoder unit with the assist of terahertz optical asymmetric demultiplexer (TOAD) is presented. The all-optical 2-to-4 decoder with a set of all-optical switches is designed which can be used to ...An all-optical 2-to-4 decoder unit with the assist of terahertz optical asymmetric demultiplexer (TOAD) is presented. The all-optical 2-to-4 decoder with a set of all-optical switches is designed which can be used to achieve a high-speed central processor unit using optical hardware. The unique output lines can be used for all-optical header processing. We attempt to develop an integrated all-optical circuit which can perform decoding of signal. This scheme is very simple and flexible for performing different logic operation and to design advanced complex logic. Simulated results are confirming the described methods.展开更多
Recently, the diffractive optics has extensively attracted interest of researchers be-cause diffractive optical elements (DOE’s) can achieve the incorporation of several opti-ca functions. Various mathematical algori...Recently, the diffractive optics has extensively attracted interest of researchers be-cause diffractive optical elements (DOE’s) can achieve the incorporation of several opti-ca functions. Various mathematical algorithms for the design of DOE’s have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 polarization-insensitive 40-Gb/s time-division demultiplexer was demonstrated in a polarization-diversity loop configuration. The power penalty was measured to be 2.3 dB at a bit error rates of 10-9 for 10 Gb/s outp...A polarization-insensitive 40-Gb/s time-division demultiplexer was demonstrated in a polarization-diversity loop configuration. The power penalty was measured to be 2.3 dB at a bit error rates of 10-9 for 10 Gb/s output signals.展开更多
A compact hybrid subsystem of 16channel optical demultiplexer, 2x2 switches, optical power monitors and control circuit board is developed. The subsystem is able to add or drop arbitrary optical channels and monitor t...A compact hybrid subsystem of 16channel optical demultiplexer, 2x2 switches, optical power monitors and control circuit board is developed. The subsystem is able to add or drop arbitrary optical channels and monitor the optical power level by software commands. The size of the subsystem is 170x200x30(mm).展开更多
In this paper,we have proposed a hybrid optical wavelength demultiplexer and power combiner for a hybrid timeand wavelength-division multiplexing(TWDM)passive optical network(PON),i.e.,a single passive optical device ...In this paper,we have proposed a hybrid optical wavelength demultiplexer and power combiner for a hybrid timeand wavelength-division multiplexing(TWDM)passive optical network(PON),i.e.,a single passive optical device that functions as a 1×N wavelength demultiplexer for distributing the downstream signal in multiple wavelengths from the optical line terminal(OLT)to the N optical network units(ONUs),and simultaneously as an N×1 power combiner for collecting the upstream signal in the same wavelength from the N ONUs to the OLT.Through a design example of a 32 channel hybrid optical wavelength demultiplexer and power combiner on the silicon-on-insulator platform,our numerical simulation result shows that the insertion loss and adjacent channel crosstalk of the downstream wavelength demultiplexer are as low as 4.6 and-16.3 dB,respectively,while the insertion loss and channel non-uniformity of the upstream power combiner can reach 3.5 and 2.1 dB,respectively.The proposed structure can readily be extended to other material platforms such as the silica-based planar lightwave circuit.Its fabrication process is fully compatible with standard clean-room technologies such as photolithography and etching,without any complicated and/or costly approach involved.展开更多
基金supported by the National Natural Science Foundation of China(Grants No.62005231)Fundamental Research Funds for the Central Universities(20720210045,20720200074)Guangdong Basic and Applied Basic Research Foundation(2021A1515012199).
文摘Miniaturized spectrometers have been widely researched in recent years,but few studies are conducted with on-chip multimode schemes for mode-division multiplexing(MDM)systems.Here we propose an ultracompact mode-division demultiplexing spectrometer that includes branched waveguide structures and graphene-based photodetectors,which realizes simultaneously spectral dispersing and light fields detecting.In the bandwidth of 1500-1600 nm,the designed spectrometer achieves the single-mode spectral resolution of 7 nm for each mode of TE_(1)-TE_(4) by Tikhonov regularization optimization.Empowered by deep learning algorithms,the 15-nm resolution of parallel reconstruction for TE_(1)-TE_(4) is achieved by a single-shot measurement.Moreover,by stacking the multimode response in TE_(1)-TE_(4) to the single spectra,the 3-nm spectral resolution is realized.This design reveals an effective solution for on-chip MDM spectroscopy,and may find applications in multimode sensing,interconnecting and processing.
基金Army Research Office(ARO)(W911NF1710500,W911NF1710553)
文摘We propose a mode demultiplexing hybrid(MDH) that integrates mode demultiplexing, local oscillator power splitting, and optical 90-deg mixing using multi-plane light conversion(MPLC). We demonstrate the realization of a three-mode MDH using four phase plates, one more than what is required for an MPLC-based mode demultiplexer, via numerical simulations. The performance of the three-mode MDH is comparable to that of commercial single-mode 90-deg hybrids. This multiple-functionality device enables simplification of the coherent optical front end of mode-division multiplexing receivers.
基金supported by National 863 High TechnologyProjects of China (No. 2007AA01Z258, 2008AA01Z15)National Natural Science Foundation of China (No.60577034, 60747002,60877042)Science Foundation of Beijing(No.4062027).
文摘The demultiplexing experiment from a 40 Gb/s optical time-division multiplexing signal is completed by using electro- absorption sampling window based on electronic phase-locked loop circuit for clock recovery. Error-free demultiplexing is achieved when the launched optical power into electro-absorption sampling window reaches 5.5 dBm without optical filter following the EDFA.
文摘An 8×2.5Gb/s 100km optical time division multiplexing(OTDM) experiment system is reported, which employs an electrical filter with high Q value for clock extraction, a nonlinear optical loop mirror(NOLM) for demultiplering and chirped fiber grating for dispersion compensation. The error free operation is achieved and the experiment results are given.
文摘We in this paper propose a model to increase the diffraction efficiency of a holographic grating at 1550 nm for multiplexing application. To use such a grating, polarization dependence loss is introduced analytically and then optimized for its minimum value A configuration of holographic grating is proposed based on both maximum diffraction efficiency and minimum polarization dependence loss. The proposed grating is expected to find importance in optoelectronic multichip module.
基金Project is supported by the National Natural Science Foundation of China (Grant No. 61804148)the National Key Research and Development Program of China (Grant No. 2018YFB2200202)。
文摘A compact and fabrication friendly polarization demultiplexer(P-DEMUX) is proposed and characterized to enable wavelength-division-multiplexing and polarization-division-multiplexing simultaneously. The proposed structure is composed of a polarization-selective microring resonator in ultrathin waveguide and two bus channels in the silicon nitridesilica-silicon horizontal slot waveguides. In the slot waveguide, the transverse electric(TE) mode propagates through the silicon layer, while the transverse magnetic(TM) mode is confined in the slot region. In the designed ultra-thin waveguide, the TM mode is cut-off. The effective indexes of the TE modes for ultrathin and slot waveguides have comparable values. Thanks for these distinguishing features, the input TE mode can be efficiently filtered through the ultra-thin microring at the resonant wavelength, while the TM mode can directly output from the through port. Simulation results show that the extinction ratio of the proposed P-DEMUX for TE and TM modes are 33.21 dB and 24.97 dB, and the insertion losses are 0.346 dB and 0.324 dB, respectively, at the wavelength of 1551.64 nm. Furthermore, the device shows a broad bandwidth(> 100 nm) for an extinction ratio(ER) of > 20 dB. In addition, the proposed P-DEMUX also has a good fabrication tolerance for the waveguide width variation of-20 nm≤ △w_(g)≤ 20 nm and the microring width variation of -20 nm≤ △w_(r) ≤20 nm for a low insertion loss of < 0.75 dB and low ER of <-18 dB.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11935010 and 11775159)the Shanghai Science and Technology Committee,China(Grant Nos.18ZR1442800 and 18JC1410900)the Opening Project of Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology.
文摘We propose the concept of thermal demultiplexer, which can split the heat flux in different frequency ranges intodifferent directions. We demonstrate this device concept in a honeycomb lattice with dangling atoms. From the view ofeffective negative mass, we give a qualitative explanation of how the dangling atoms change the original transport property.We first design a two-mass configuration thermal demultiplexer, and find that the heat flux can flow into different ports incorresponding frequency ranges roughly. Then, to improve the performance, we choose the suitable masses of danglingatoms and optimize the four-mass configuration with genetic algorithm. Finally, we give out the optimal configuration witha remarkable effect. Our study finds a way to selectively split spectrum-resolved heat to different ports as phonon splitter,which would provide a new means to manipulate phonons and heat, and to guide the design of phononic thermal devices inthe future.
文摘We investigate the electronic transport in a simple mesoscopic cross structure made of two wires(stubs)grafted at the same point along a quantum waveguide.We show that the structure may exhibit important phenomena such as bound in continuum(BIC)states.These states are transformed into electromagnetically induced transparency(EIT)resonance by detuning slightly the lengths of the stubs.The last phenomenon is used to propose and study a mesoscopic demultiplexer device with an input waveguide and two output waveguides.We give closed-form expressions of the geometrical parameters that allow a selective transfer of a given state in the first waveguide without perturbing the second waveguide.The effect of temperature on the transmission resonances is also examined by using Landauer-Büttiker formula.The analytical results of the dispersion relation and transmission and reflection coefficient are obtained using the Green's function method.
文摘Fiber optic Mach Zehnder interferometer(MZI) can be used as wavelength multiplexers and demultiplexers. The △ L and △ directly influence the properties of MZI. To lengthen the △ L can demultiplex much more wavelengths, but when the △ L is longer, the temperature will influence MZI more seriously. A method to solve this problem is proposed, which enables MZI to work stably. The wavelength distance is 0.8 nm, and the extinction ratio is high.
文摘In many domains of science and technology, as the need for secured transmission of information has grown over the years, a variety of methods have been studied and devised to achieve this goal. In this paper, we present an information securing method using chaos encryption. Our proposal uses only one chaotic oscillator both for signal encryption and decryption for?avoiding the delicate synchronisation step. We carried out numerical and electronic simulations of the proposed circuit using electrocardiographic signals as input. Results obtained from both simulations were compared and exhibited a good agreement proving the suitability of our system for signal encryption and decryption.
文摘Using Terahertz Optical Asymmetric Demultiplexer (TOAD) based switch we have designed all-optical parallel half adder and full adder. The approach to design this all-optical arithmetic circuit not only enhances the computational speed but also is capable of synthesizing light as input to produce desire output. The main advantage of parallel circuit is synchronization of input which is not required. All the circuits are designed theoretically and verified through numerical simulations.
文摘An all-optical 3:8 decoder unit with the help of terahertz optical asymmetric demultiplexer (TOAD) is proposed. The all-optical 3:8 decoder unit with a set of all-optical full-adders and optical exclusive-ORs (XORs), can be used to perform a fast central processor unit using optical hardware components. We try to exploit the advantages of TOAD-based optical switch to design an integrated all-optical circuit which can perform decoding of signal. A theoretical model is presented and verified through numerical simulation. The new method promises both higher processing speed and accuracy. The model can be extended for studying more complex all-optical circuit of enhanced functionality in which decoder is the basic building block. The operation of the proposed circuit is parallel in nature. The impact of the switching energy with small signal gain and variation of extinction ratio and contrast ration with control pulse energy of the switching outcome is explored and assessed by means of numerical simulations.
文摘An all-optical 2-to-4 decoder unit with the assist of terahertz optical asymmetric demultiplexer (TOAD) is presented. The all-optical 2-to-4 decoder with a set of all-optical switches is designed which can be used to achieve a high-speed central processor unit using optical hardware. The unique output lines can be used for all-optical header processing. We attempt to develop an integrated all-optical circuit which can perform decoding of signal. This scheme is very simple and flexible for performing different logic operation and to design advanced complex logic. Simulated results are confirming the described methods.
基金Project supported by the National Natural Science Foundation of China in part by the Chinese Academy of Sciences.
文摘Recently, the diffractive optics has extensively attracted interest of researchers be-cause diffractive optical elements (DOE’s) can achieve the incorporation of several opti-ca functions. Various mathematical algorithms for the design of DOE’s have
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 polarization-insensitive 40-Gb/s time-division demultiplexer was demonstrated in a polarization-diversity loop configuration. The power penalty was measured to be 2.3 dB at a bit error rates of 10-9 for 10 Gb/s output signals.
文摘A compact hybrid subsystem of 16channel optical demultiplexer, 2x2 switches, optical power monitors and control circuit board is developed. The subsystem is able to add or drop arbitrary optical channels and monitor the optical power level by software commands. The size of the subsystem is 170x200x30(mm).
文摘In this paper,we have proposed a hybrid optical wavelength demultiplexer and power combiner for a hybrid timeand wavelength-division multiplexing(TWDM)passive optical network(PON),i.e.,a single passive optical device that functions as a 1×N wavelength demultiplexer for distributing the downstream signal in multiple wavelengths from the optical line terminal(OLT)to the N optical network units(ONUs),and simultaneously as an N×1 power combiner for collecting the upstream signal in the same wavelength from the N ONUs to the OLT.Through a design example of a 32 channel hybrid optical wavelength demultiplexer and power combiner on the silicon-on-insulator platform,our numerical simulation result shows that the insertion loss and adjacent channel crosstalk of the downstream wavelength demultiplexer are as low as 4.6 and-16.3 dB,respectively,while the insertion loss and channel non-uniformity of the upstream power combiner can reach 3.5 and 2.1 dB,respectively.The proposed structure can readily be extended to other material platforms such as the silica-based planar lightwave circuit.Its fabrication process is fully compatible with standard clean-room technologies such as photolithography and etching,without any complicated and/or costly approach involved.