In recent years,the use of deep learning to replace traditional numerical methods for electromagnetic propagation has shown tremendous potential in the rapid design of photonic devices.However,most research on deep le...In recent years,the use of deep learning to replace traditional numerical methods for electromagnetic propagation has shown tremendous potential in the rapid design of photonic devices.However,most research on deep learning has focused on single-layer grating couplers,and the accuracy of multi-layer grating couplers has not yet reached a high level.This paper proposes and demonstrates a novel deep learning network-assisted strategy for inverse design.The network model is based on a multi-layer perceptron(MLP)and incorporates convolutional neural networks(CNNs)and transformers.Through the stacking of multiple layers,it achieves a high-precision design for both multi-layer and single-layer raster couplers with various functionalities.The deep learning network exhibits exceptionally high predictive accuracy,with an average absolute error across the full wavelength range of 1300–1700 nm being only 0.17%,and an even lower predictive absolute error below 0.09%at the specific wavelength of 1550 nm.By combining the deep learning network with the genetic algorithm,we can efficiently design grating couplers that perform different functions.Simulation results indicate that the designed single-wavelength grating couplers achieve coupling efficiencies exceeding 80%at central wavelengths of 1550 nm and 1310 nm.The performance of designed dual-wavelength and broadband grating couplers also reaches high industry standards.Furthermore,the network structure and inverse design method are highly scalable and can be applied not only to multi-layer grating couplers but also directly to the prediction and design of single-layer grating couplers,providing a new perspective for the innovative development of photonic devices.展开更多
A high efficiency and broad bandwidth grating coupler between a silicon-on-insulator （SOI） nanophotonic waveguide and fibre is designed and fabricated. Coupling efficiencies of 46% and 25% at a wavelength of 1.55um ...A high efficiency and broad bandwidth grating coupler between a silicon-on-insulator （SOI） nanophotonic waveguide and fibre is designed and fabricated. Coupling efficiencies of 46% and 25% at a wavelength of 1.55um are achieved by simulation and experiment, respectively. An optical 3 dB bandwidth of 45 mn from 1530 nm to 1575 nm is also obtained in experin, ent. Numerical calculation shows that a tolerance to fabrication error of 10 nm in etch depth is achievable. The measurement results indicate that the alignment error of 112 um results in less than 1 dB additional coupling loss.展开更多
A novel grating coupler with a stair-step blaze profile is proposed. The coupler is a CMOS process compatible device and can be used for light coupling in optical communication. The blaze profile can be optimized to o...A novel grating coupler with a stair-step blaze profile is proposed. The coupler is a CMOS process compatible device and can be used for light coupling in optical communication. The blaze profile can be optimized to obtain a high efficiency of 66.7% for the out-of-plane coupling at the centre wavelength of 1595 nm with a 1 dB bandwidth of 41 nm. Five key parameters of the stair-step blaze grating and their effects on the coupling are discussed for the application in L band telecommunication.展开更多
The scalar two-dimensional finite difference time domain (FDTD) method is applied to simulate the mode field distribution of TE 0 of the waveguide grating coupler. Computer simulation shows that the same stable mode f...The scalar two-dimensional finite difference time domain (FDTD) method is applied to simulate the mode field distribution of TE 0 of the waveguide grating coupler. Computer simulation shows that the same stable mode field distribution pattern is obtained through the different kinds of driving sources. It is found that the optical field mode is determined by waveguide structure and optical wavelength other than the driving source.According to the mode field distribution, the optimum coupling efficiency can be predicted. Compared with another numerical methods,the CPU-time and memory elements of computer used by FDTD are much less.展开更多
A novel high-efficiency focusing non-uniform grating coupler is proposed to couple light into or off silicon photonic chips for large-scale silicon photonic integration. This kind of grating coupler decreases the tran...A novel high-efficiency focusing non-uniform grating coupler is proposed to couple light into or off silicon photonic chips for large-scale silicon photonic integration. This kind of grating coupler decreases the transition length of the linking taper between the grating and the single-mode waveguide by at least 80%. The radian of the grating lines and the size of the taper are optimized to improve the coupling efficiency. An experimental coupling efficiency of ~ 68% at 1556.24 nm is obtained after optimization and the whole size of the grating is 12 μm × 30 μm, with a very short taper transition of ~15 μm long.展开更多
Grating couplers are widely investigated as coupling interfaces between silicon-on-insulator waveguides and optical fibers.In this work,a high-efficiency and complementary metal-oxide-semiconductor（CMOS） process com...Grating couplers are widely investigated as coupling interfaces between silicon-on-insulator waveguides and optical fibers.In this work,a high-efficiency and complementary metal-oxide-semiconductor（CMOS） process compatible grating coupler is proposed.The poly-Si layer used as a gate in the CMOS metal-oxide-semiconductor field effect transistor（MOSFET） is combined with a normal fully etched grating coupler,which greatly enhances its coupling efficiency.With optimal structure parameters,a coupling efficiency can reach as high as ～ 70% at a wavelength of 1550 nm as indicated by simulation.From the angle of fabrication,all masks and etching steps are shared between MOSFETs and grating couplers,thereby making the high performance grating couplers easily integrated with CMOS circuits.Fabrication errors such as alignment shift are also simulated,showing that the device is quite tolerant in fabrication.展开更多
A two-dimensional apodized grating coupler for interfacing between single-mode fiber and photonic circuit is demonstrated in order to bridge the mode gap between the grating coupler and optical fiber. The grating groo...A two-dimensional apodized grating coupler for interfacing between single-mode fiber and photonic circuit is demonstrated in order to bridge the mode gap between the grating coupler and optical fiber. The grating grooves of the grating couplers are realized by columns of fully etched nanostructures, which are utilized to digitally tailor the effective refractive index of each groove in order to obtain the Gaussian-like output diffractive mode and then enhance the coupling efficiency.Compared with that of the uniform grating coupler, the coupling efficiency of the apodized grating coupler is increased by 4.3% and 5.7%, respectively, for the nanoholes and nanorectangles as refractive index tunes layer.展开更多
A novel highly efficient grating coupler with large filling factor and deep etching is proposed in silicon-on-insulator for near vertical coupling between the rib waveguide and optical fibre. The deep slots acting as ...A novel highly efficient grating coupler with large filling factor and deep etching is proposed in silicon-on-insulator for near vertical coupling between the rib waveguide and optical fibre. The deep slots acting as high efficient scattering centres are analysed and optimized. As high as 60% coupling efficiency at telecom wavelength of 1550-nm and 3-dB bandwidth of 61 nm are predicted by simulation. A peak coupling efficiency of 42.1% at wavelength 1546-nm and 3-dB bandwidth of 37.6 nm are obtained experimentally.展开更多
We design and demonstrate a one-dimensional grating coupler with a low polarization-dependent loss(PDL)for large spatial light spots.Based on current fabrication conditions,we first utilize genetic algorithms to find ...We design and demonstrate a one-dimensional grating coupler with a low polarization-dependent loss(PDL)for large spatial light spots.Based on current fabrication conditions,we first utilize genetic algorithms to find the optimal grating structure including the distributions of duty and periods,making the effective refractive index of transverse electric mode the same as that of transverse magnetic mode.The designed grating coupler is fabricated on the common silicon-on-insulator platform and the PDL is measured to be within 0.41 d B covering the C-band.展开更多
Mid-infrared(mid-IR)silicon photonic integrated circuits have drawn considerable interest to date.However,previous devices are typically designed on silicon waveguide configurations with hundreds of nanometers in thic...Mid-infrared(mid-IR)silicon photonic integrated circuits have drawn considerable interest to date.However,previous devices are typically designed on silicon waveguide configurations with hundreds of nanometers in thickness,hindering their application in sensing.Here,we demonstrated a suspended nanomembrane silicon(SNS)microring resonator(MRR)at 3.27μm wavelengths with a subwavelength grating coupler.Our experimental results show that the SNS MRR showcases a quality factor of~3500 with a giant confinement factor of 0.89 and reduced thermal sensitivity of 0.07 nm/℃.To our knowledge,the study opens a new avenue to developing mid-IR silicon devices for sensing applications.展开更多
We propose and demonstrate a polarization diversity two-dimensional grating coupler based on the lithium niobate on insulator platform, for the first time, to the best of our knowledge. The optimization design, perfor...We propose and demonstrate a polarization diversity two-dimensional grating coupler based on the lithium niobate on insulator platform, for the first time, to the best of our knowledge. The optimization design, performance characteristics,and fabrication tolerance of the two-dimensional grating coupler are thoroughly analyzed utilizing the three-dimensional finite-difference time-domain method. Experimentally,-7.2 d B of coupling efficiency is achieved with 1 d B bandwidth of64 nm. The polarization-dependent loss is about 0.4 d B around 1550 nm. Our work provides new polarization multiplexing approaches for the lithium niobate on insulator platform, paving the way for critical applications such as high-speed polarization multiplexed electro-optical modulators.展开更多
We present the design of a diffractive grating structure and get the optimal parameters which can achieve more than 75%coupling efficiency（CE） between single-mode fiber and silicon-on-insulator（SOI） waveguide thro...We present the design of a diffractive grating structure and get the optimal parameters which can achieve more than 75%coupling efficiency（CE） between single-mode fiber and silicon-on-insulator（SOI） waveguide through 2D finite-different time-domain（FDTD） simulation.The proposed architecture has a uniform structure with no bottom reflection element or silicon overlay.The structure,including grating couplers,adiabatic tapers and interconnection waveguides can be fabricated on the SOI waveguide with only a single electron-beam lithography（ICP） step,which is CMOS-compatible.A relatively high coupling efficiency of 47.2%was obtained at a wavelength of 1562 nm.展开更多
In this paper,we report on polarization combining two-dimensional grating couplers(2D GCs)on amorphous Si:H,fabricated in the backend of line of a photonic BiCMOS platform.The 2D GCs can be used as an interface of a h...In this paper,we report on polarization combining two-dimensional grating couplers(2D GCs)on amorphous Si:H,fabricated in the backend of line of a photonic BiCMOS platform.The 2D GCs can be used as an interface of a hybrid silicon photonic coherent transmitter,which can be implemented on bulk Si wafers.The fabricated 2D GCs operate in the telecom C-band and show an experimental coupling efficiency of−5 dB with a wafer variation of±1.2 dB.Possibilities for efficiency enhancement and improved performance stability in future design generations are outlined and extension toward O-band devices is also investigated.展开更多
A high-performance grating coupler(GC) operating at a wavelength of 1550 nm is proposed by utilizing the adjoint-based inverse design algorithm on a 220 nm silicon-on-insulator(SOI) substrate. The grating scheme offer...A high-performance grating coupler(GC) operating at a wavelength of 1550 nm is proposed by utilizing the adjoint-based inverse design algorithm on a 220 nm silicon-on-insulator(SOI) substrate. The grating scheme offers several advantages,including simple structure, large minimum feature size(MFS), manufacturing friendliness, support for large-scale production and multi-project wafer (MPW) runs, etc., while simultaneously maintaining exceptional coupling performance and fabrication tolerance. The design process incorporates various fabrication constraints to satisfy the specifications of different foundry processes. The optimized GC demonstrates excellent coupling performance and 3 d B bandwidth within the MFS range of 60 to 180 nm. The simulated coupling efficiency(CE) of the GC with 130 nm MFS is-1.69 dB, whereas the experimentally measured CE of the fabricated GC using electron beam lithography(EBL) is-2.83 dB. Notably, the experimental CE of the GC with 180 nm MFS fabricated using 248 nm deep ultraviolet(DUV) lithography is-2.77 dB, representing the highest experimental CE ever reported for a single-layer etching C-Band GC supported by MPW runs fabricated on 220 nm SOI without utilizing any back reflector, multi-etch layer, or overlay. The manufacturing outcomes of the same GC structure employing different manufacturing processes are discussed and analyzed, providing valuable insights for the fabrication of silicon photonics devices.展开更多
An ultra-small integrated photonic circuit has been proposed,which incorporates a high-quality-factor passive micro-ring resonator（MR） linked to a vertical grating coupler on a standard silicon-on-insulator（SOI） s...An ultra-small integrated photonic circuit has been proposed,which incorporates a high-quality-factor passive micro-ring resonator（MR） linked to a vertical grating coupler on a standard silicon-on-insulator（SOI） substrate.The experimental results demonstrate that the MR propagation loss is 0.532 dB/cm with a 10μm radius ring resonator,the intrinsic quality factor is as high as 202.000,the waveguide grating wavelength response curve is a 1 dB bandwidth of 40 nm at 1540 nm telecommunication wavelengths,and the measured fiber-to-fiber coupling loss is 10 dB.Furthermore,the resonator wavelength temperature dependence of the 450 nm wide micro-ring resonator is 54.1 pm/℃.Such vertical grating coupler and low loss MR-integrated components greatly promote a key element in biosensors and high-speed interconnect communication applications.展开更多
We theoretically investigated laser trimming to adjust grating offset in phase-shifted fiber grating coupler (FGC) for all-optical switching application. It was clarified that the trimming made the extinction ratio hi...We theoretically investigated laser trimming to adjust grating offset in phase-shifted fiber grating coupler (FGC) for all-optical switching application. It was clarified that the trimming made the extinction ratio higher in all-optical FGC switch.展开更多
In this paper,we provide an overview and comparison of devices used for optical waveguide-to-waveguide coupling including inter-chip edge couplers,grating couplers,free form couplers,evanescent couplers,cantilever cou...In this paper,we provide an overview and comparison of devices used for optical waveguide-to-waveguide coupling including inter-chip edge couplers,grating couplers,free form couplers,evanescent couplers,cantilever couplers,and optical wirebonds.In addition,technology for efficient transmission of light through chips is discussed including guided mode and free form photonic vias for substrates including silicon,glass,and organics.The results are discussed in the context of potential applications including co-packaged optics switch packages,replaceable biochemical sensors,optically connected memory,optical computing,integrated quantum photonics,and integrated LiDAR systems to show possible improvements in energy efficiency,performance,and cost.展开更多
In this paper, a tension insensitive Pb S fiber temperature sensor based on Sagnac interferometer is proposed and demonstrated. The sensing mechanism of tension and temperature is analyzed. The relationships between t...In this paper, a tension insensitive Pb S fiber temperature sensor based on Sagnac interferometer is proposed and demonstrated. The sensing mechanism of tension and temperature is analyzed. The relationships between the interference spectrum, temperature and tension are analyzed, respectively. The experimental temperature range is 36—70 °C. The experimental results show that the interference spectrum is red shifted, and its sensitivity is 53.89 pm/°C. In tension experiment, the tension range is 0—1 400 με. The experimental results show that there is no wavelength shift in the interference spectrum. The sensor is immune to tension cross-sensitivity compared with other sensors. It can be used for temperature testing in aerospace, chemistry and pharmacy.展开更多
We report an efficient continuous-wave self-Raman laser at 1176 nm based on a 20-mm-long composite YVO4/Nd：YVO4/YVO4 crystal and pumped by a wavelength-locked 878.9 nm diode laser.A maximum output power of 5.3 W is a...We report an efficient continuous-wave self-Raman laser at 1176 nm based on a 20-mm-long composite YVO4/Nd：YVO4/YVO4 crystal and pumped by a wavelength-locked 878.9 nm diode laser.A maximum output power of 5.3 W is achieved at a pump power of 26 W,corresponding to an optical conversion efficiency of 20%and a slope efficiency of 21%.The Raman threshold for the diode pump power was only 0.92 W.The results reveal that in-band pumping by a wavelength-locked diode laser significantly enhances output power and efficiency of self-Raman lasers by virtue of improved pump absorption and relieved thermal loading.展开更多
A switchable dual-wavelength erbium-doped fiber laser(EDFL) with tunable wavelength is demonstrated. The ring cavity consists of two branches with a fiber Bragg grating(FBG) and a spherical-shape structure as fiber fi...A switchable dual-wavelength erbium-doped fiber laser(EDFL) with tunable wavelength is demonstrated. The ring cavity consists of two branches with a fiber Bragg grating(FBG) and a spherical-shape structure as fiber filters, respectively. By adjusting the variable optical attenuator(VOA), the laser can be switched between the single-wavelength mode and the dual-wavelength mode. The spherical-shape structure has good sensitivity to the temperature. When the temperature changes from 30 °C to 190 °C, the central wavelength of the EDFL generated by the branch of spherical-shape structure varies from 1 551.6 nm to 1 561.8 nm, which means that the wavelength interval is tunable.展开更多
基金sponsored by the National Key Scientific Instrument and Equipment Development Projects of China(Grant No.62027823)the National Natural Science Foun-dation of China(Grant No.61775048).
文摘In recent years,the use of deep learning to replace traditional numerical methods for electromagnetic propagation has shown tremendous potential in the rapid design of photonic devices.However,most research on deep learning has focused on single-layer grating couplers,and the accuracy of multi-layer grating couplers has not yet reached a high level.This paper proposes and demonstrates a novel deep learning network-assisted strategy for inverse design.The network model is based on a multi-layer perceptron(MLP)and incorporates convolutional neural networks(CNNs)and transformers.Through the stacking of multiple layers,it achieves a high-precision design for both multi-layer and single-layer raster couplers with various functionalities.The deep learning network exhibits exceptionally high predictive accuracy,with an average absolute error across the full wavelength range of 1300–1700 nm being only 0.17%,and an even lower predictive absolute error below 0.09%at the specific wavelength of 1550 nm.By combining the deep learning network with the genetic algorithm,we can efficiently design grating couplers that perform different functions.Simulation results indicate that the designed single-wavelength grating couplers achieve coupling efficiencies exceeding 80%at central wavelengths of 1550 nm and 1310 nm.The performance of designed dual-wavelength and broadband grating couplers also reaches high industry standards.Furthermore,the network structure and inverse design method are highly scalable and can be applied not only to multi-layer grating couplers but also directly to the prediction and design of single-layer grating couplers,providing a new perspective for the innovative development of photonic devices.
基金Project supported in part by the National Natural Science Foundation of China (Grant Nos. 60537010 and 60877036)the National Basic Research Program of China (Grant No. 2006CB302803)the Knowledge Innovation Program of Institute of Semiconductors, Chinese Academy of Sciences (ISCAS) (Grant No. ISCAS2008T10)
文摘A high efficiency and broad bandwidth grating coupler between a silicon-on-insulator （SOI） nanophotonic waveguide and fibre is designed and fabricated. Coupling efficiencies of 46% and 25% at a wavelength of 1.55um are achieved by simulation and experiment, respectively. An optical 3 dB bandwidth of 45 mn from 1530 nm to 1575 nm is also obtained in experin, ent. Numerical calculation shows that a tolerance to fabrication error of 10 nm in etch depth is achievable. The measurement results indicate that the alignment error of 112 um results in less than 1 dB additional coupling loss.
基金Project supported by the National Natural Science Foundation of China (Grant No.60877036)the National Basic Research Program of China (Grant Nos.2006CB302803 and 2011CB301701)+1 种基金the State Key Laboratory of Advanced Optical Communication Systems and Networks,China (Grant No.2008SH02)the Knowledge Innovation Program of Institute of Semiconductors,Chinese Academy of Sciences (Grant No.ISCAS2008T10)
文摘A novel grating coupler with a stair-step blaze profile is proposed. The coupler is a CMOS process compatible device and can be used for light coupling in optical communication. The blaze profile can be optimized to obtain a high efficiency of 66.7% for the out-of-plane coupling at the centre wavelength of 1595 nm with a 1 dB bandwidth of 41 nm. Five key parameters of the stair-step blaze grating and their effects on the coupling are discussed for the application in L band telecommunication.
文摘The scalar two-dimensional finite difference time domain (FDTD) method is applied to simulate the mode field distribution of TE 0 of the waveguide grating coupler. Computer simulation shows that the same stable mode field distribution pattern is obtained through the different kinds of driving sources. It is found that the optical field mode is determined by waveguide structure and optical wavelength other than the driving source.According to the mode field distribution, the optimum coupling efficiency can be predicted. Compared with another numerical methods,the CPU-time and memory elements of computer used by FDTD are much less.
基金supported by the National Basic Research Program of China(Grant No.2011CB301701)the National High Technology Research and Development Program of China(Grant No.2012AA012202)+1 种基金the Main Direction Program of Knowledge Innovation of the Chinese Academy of Sciences(Grant No.KGCX2-EW-102)the National Natural Science Foundation of China(Grant Nos.61107048 and 61275065)
文摘A novel high-efficiency focusing non-uniform grating coupler is proposed to couple light into or off silicon photonic chips for large-scale silicon photonic integration. This kind of grating coupler decreases the transition length of the linking taper between the grating and the single-mode waveguide by at least 80%. The radian of the grating lines and the size of the taper are optimized to improve the coupling efficiency. An experimental coupling efficiency of ~ 68% at 1556.24 nm is obtained after optimization and the whole size of the grating is 12 μm × 30 μm, with a very short taper transition of ~15 μm long.
基金Project supported by the Natural Science Foundation of Shanghai,China (Grant No. 11ZR1443700)the Funds from the Science and Technology Commission of Shanghai Municipality,China (Grant Nos. 10DJ1400400 and 10706200500)the National Natural Science Foundation of China (Grant No. 61106051)
文摘Grating couplers are widely investigated as coupling interfaces between silicon-on-insulator waveguides and optical fibers.In this work,a high-efficiency and complementary metal-oxide-semiconductor（CMOS） process compatible grating coupler is proposed.The poly-Si layer used as a gate in the CMOS metal-oxide-semiconductor field effect transistor（MOSFET） is combined with a normal fully etched grating coupler,which greatly enhances its coupling efficiency.With optimal structure parameters,a coupling efficiency can reach as high as ～ 70% at a wavelength of 1550 nm as indicated by simulation.From the angle of fabrication,all masks and etching steps are shared between MOSFETs and grating couplers,thereby making the high performance grating couplers easily integrated with CMOS circuits.Fabrication errors such as alignment shift are also simulated,showing that the device is quite tolerant in fabrication.
基金supported by the National Natural Science Foundation of China(Grant Nos.61222501,61335004,and 61505003)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20111103110019)+1 种基金the Postdoctoral Science Foundation of Beijing Funded Project,China(Grant No.Q6002012201502)the Science and Technology Research Project of Jiangxi Provincial Education Department,China(Grant No.GJJ150998)
文摘A two-dimensional apodized grating coupler for interfacing between single-mode fiber and photonic circuit is demonstrated in order to bridge the mode gap between the grating coupler and optical fiber. The grating grooves of the grating couplers are realized by columns of fully etched nanostructures, which are utilized to digitally tailor the effective refractive index of each groove in order to obtain the Gaussian-like output diffractive mode and then enhance the coupling efficiency.Compared with that of the uniform grating coupler, the coupling efficiency of the apodized grating coupler is increased by 4.3% and 5.7%, respectively, for the nanoholes and nanorectangles as refractive index tunes layer.
基金Project supported in part by the National Natural Science Foundation of China(Grant No.60877036)the National Basic Research Program of China(Grant No.2006CB302803)+1 种基金the Foundation of the State Key Laboratory of Advanced Optical Communication Systems and Networks,China(Grant No.2008SH02)the Knowledge Innovation Program of Institute of Semiconductors, Chinese Academy of Sciences(Grant No.ISCAS2008T10)
文摘A novel highly efficient grating coupler with large filling factor and deep etching is proposed in silicon-on-insulator for near vertical coupling between the rib waveguide and optical fibre. The deep slots acting as high efficient scattering centres are analysed and optimized. As high as 60% coupling efficiency at telecom wavelength of 1550-nm and 3-dB bandwidth of 61 nm are predicted by simulation. A peak coupling efficiency of 42.1% at wavelength 1546-nm and 3-dB bandwidth of 37.6 nm are obtained experimentally.
基金Project supported by the National High Technology Research and Development Program of China(Grant No.18-H863-04-ZD-006-007-01)。
文摘We design and demonstrate a one-dimensional grating coupler with a low polarization-dependent loss(PDL)for large spatial light spots.Based on current fabrication conditions,we first utilize genetic algorithms to find the optimal grating structure including the distributions of duty and periods,making the effective refractive index of transverse electric mode the same as that of transverse magnetic mode.The designed grating coupler is fabricated on the common silicon-on-insulator platform and the PDL is measured to be within 0.41 d B covering the C-band.
基金supported by the National Natural Science Foundation of China(Nos.62175179,62161160335,and 62475188)the Natural Science Foundation of Tianjin Municipality,China(No.23JCJQJC00250)the Natural Science Foundation of Guangdong Province,China(Nos.2022B1515130002 and 2023A1515011189)。
文摘Mid-infrared(mid-IR)silicon photonic integrated circuits have drawn considerable interest to date.However,previous devices are typically designed on silicon waveguide configurations with hundreds of nanometers in thickness,hindering their application in sensing.Here,we demonstrated a suspended nanomembrane silicon(SNS)microring resonator(MRR)at 3.27μm wavelengths with a subwavelength grating coupler.Our experimental results show that the SNS MRR showcases a quality factor of~3500 with a giant confinement factor of 0.89 and reduced thermal sensitivity of 0.07 nm/℃.To our knowledge,the study opens a new avenue to developing mid-IR silicon devices for sensing applications.
基金supported in part by the National Key R&D Program of China(Nos.2019YFB1803900 and 2019YFA0705000)the National Natural Science Foundation of China(Nos.11690031,11761131001,and 11904061)+6 种基金the Key R&D Program of Guangdong Province(No.2018B030329001)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01X121)the Project of Key Laboratory of Radar Imaging and Microwave Photonics,Ministry of Education(No.RIMP2019003)the Innovation Fund of WNLO(No.2018WNLOKF010),the Guangzhou Science and Technology Program(No.201707010096)the Guangxi Youth and Middle Aged Ability Promotion Project(No.2019KY0126)the BaGui Scholar Programof Guangxi Province(No.02304002022C)the China Postdoctoral Science Foundation(No.2020M673554XB).
文摘We propose and demonstrate a polarization diversity two-dimensional grating coupler based on the lithium niobate on insulator platform, for the first time, to the best of our knowledge. The optimization design, performance characteristics,and fabrication tolerance of the two-dimensional grating coupler are thoroughly analyzed utilizing the three-dimensional finite-difference time-domain method. Experimentally,-7.2 d B of coupling efficiency is achieved with 1 d B bandwidth of64 nm. The polarization-dependent loss is about 0.4 d B around 1550 nm. Our work provides new polarization multiplexing approaches for the lithium niobate on insulator platform, paving the way for critical applications such as high-speed polarization multiplexed electro-optical modulators.
基金Project supported by the National Key Research and Development Program of China(No.2016YFB0402404)the High-Tech Research and Development Program of China(Nos.2013AA031401,2015AA016902,2015AA016904)the National Natural Foundation of China(Nos.61674136,61435002,61176053,61274069)
文摘We present the design of a diffractive grating structure and get the optimal parameters which can achieve more than 75%coupling efficiency（CE） between single-mode fiber and silicon-on-insulator（SOI） waveguide through 2D finite-different time-domain（FDTD） simulation.The proposed architecture has a uniform structure with no bottom reflection element or silicon overlay.The structure,including grating couplers,adiabatic tapers and interconnection waveguides can be fabricated on the SOI waveguide with only a single electron-beam lithography（ICP） step,which is CMOS-compatible.A relatively high coupling efficiency of 47.2%was obtained at a wavelength of 1562 nm.
基金This work was supported in part by the German Research Foundation(DFG)through the projects EPIC-Sense(ZI 1283-6-1)EPIDAC(ZI 1283-7-1)the Federal Ministry of Education and Research(BMBF)through project PEARLS(13N14932).
文摘In this paper,we report on polarization combining two-dimensional grating couplers(2D GCs)on amorphous Si:H,fabricated in the backend of line of a photonic BiCMOS platform.The 2D GCs can be used as an interface of a hybrid silicon photonic coherent transmitter,which can be implemented on bulk Si wafers.The fabricated 2D GCs operate in the telecom C-band and show an experimental coupling efficiency of−5 dB with a wafer variation of±1.2 dB.Possibilities for efficiency enhancement and improved performance stability in future design generations are outlined and extension toward O-band devices is also investigated.
基金supported by the Shanghai Science and Technology Innovation Action Plan (No.22501100800)the SJTU Pinghu Institute of Intelligent Optoelectronics Open Foundation (No.22H010102520)。
文摘A high-performance grating coupler(GC) operating at a wavelength of 1550 nm is proposed by utilizing the adjoint-based inverse design algorithm on a 220 nm silicon-on-insulator(SOI) substrate. The grating scheme offers several advantages,including simple structure, large minimum feature size(MFS), manufacturing friendliness, support for large-scale production and multi-project wafer (MPW) runs, etc., while simultaneously maintaining exceptional coupling performance and fabrication tolerance. The design process incorporates various fabrication constraints to satisfy the specifications of different foundry processes. The optimized GC demonstrates excellent coupling performance and 3 d B bandwidth within the MFS range of 60 to 180 nm. The simulated coupling efficiency(CE) of the GC with 130 nm MFS is-1.69 dB, whereas the experimentally measured CE of the fabricated GC using electron beam lithography(EBL) is-2.83 dB. Notably, the experimental CE of the GC with 180 nm MFS fabricated using 248 nm deep ultraviolet(DUV) lithography is-2.77 dB, representing the highest experimental CE ever reported for a single-layer etching C-Band GC supported by MPW runs fabricated on 220 nm SOI without utilizing any back reflector, multi-etch layer, or overlay. The manufacturing outcomes of the same GC structure employing different manufacturing processes are discussed and analyzed, providing valuable insights for the fabrication of silicon photonics devices.
基金supported by the National Basic Research Program of China(No.2009CB326206)the National Natural Science Foundation of China(Nos.61076111,50975266)+2 种基金the Key Laboratory Fund of China(No.9140C1204040909)the Graduate Innovation Project of China (No.20103083)the Fund for Top Young Academic Leaders of Higher Learning Institutions of Shanxi(TYAL),China
文摘An ultra-small integrated photonic circuit has been proposed,which incorporates a high-quality-factor passive micro-ring resonator（MR） linked to a vertical grating coupler on a standard silicon-on-insulator（SOI） substrate.The experimental results demonstrate that the MR propagation loss is 0.532 dB/cm with a 10μm radius ring resonator,the intrinsic quality factor is as high as 202.000,the waveguide grating wavelength response curve is a 1 dB bandwidth of 40 nm at 1540 nm telecommunication wavelengths,and the measured fiber-to-fiber coupling loss is 10 dB.Furthermore,the resonator wavelength temperature dependence of the 450 nm wide micro-ring resonator is 54.1 pm/℃.Such vertical grating coupler and low loss MR-integrated components greatly promote a key element in biosensors and high-speed interconnect communication applications.
文摘We theoretically investigated laser trimming to adjust grating offset in phase-shifted fiber grating coupler (FGC) for all-optical switching application. It was clarified that the trimming made the extinction ratio higher in all-optical FGC switch.
基金supported by NSF Convergence Accelerator Track I:FUTUR-IC:A Resource-Efficient Microchip Manufacturing and Operations Research Alliance,Award Number ITE-2345076.
文摘In this paper,we provide an overview and comparison of devices used for optical waveguide-to-waveguide coupling including inter-chip edge couplers,grating couplers,free form couplers,evanescent couplers,cantilever couplers,and optical wirebonds.In addition,technology for efficient transmission of light through chips is discussed including guided mode and free form photonic vias for substrates including silicon,glass,and organics.The results are discussed in the context of potential applications including co-packaged optics switch packages,replaceable biochemical sensors,optically connected memory,optical computing,integrated quantum photonics,and integrated LiDAR systems to show possible improvements in energy efficiency,performance,and cost.
基金supported by the National Natural Science Foundation of China(Nos.61675176,61575170 and 61475133)the Research Program of Hebei Province(Nos.16961701D and F2015203270)+1 种基金the Graduate Innovation Project(Nos.2015XJSS031 and 2015XJSS028)the "XinRuiGongCheng" Talent Project of Yanshan University
文摘In this paper, a tension insensitive Pb S fiber temperature sensor based on Sagnac interferometer is proposed and demonstrated. The sensing mechanism of tension and temperature is analyzed. The relationships between the interference spectrum, temperature and tension are analyzed, respectively. The experimental temperature range is 36—70 °C. The experimental results show that the interference spectrum is red shifted, and its sensitivity is 53.89 pm/°C. In tension experiment, the tension range is 0—1 400 με. The experimental results show that there is no wavelength shift in the interference spectrum. The sensor is immune to tension cross-sensitivity compared with other sensors. It can be used for temperature testing in aerospace, chemistry and pharmacy.
基金Project supported by the Natural Science Foundation of Jiangsu Province,China(Grant Nos.BK20130453 and BK20130434)the National Natural Science Foundation of China(Grant No.11304271)
文摘We report an efficient continuous-wave self-Raman laser at 1176 nm based on a 20-mm-long composite YVO4/Nd：YVO4/YVO4 crystal and pumped by a wavelength-locked 878.9 nm diode laser.A maximum output power of 5.3 W is achieved at a pump power of 26 W,corresponding to an optical conversion efficiency of 20%and a slope efficiency of 21%.The Raman threshold for the diode pump power was only 0.92 W.The results reveal that in-band pumping by a wavelength-locked diode laser significantly enhances output power and efficiency of self-Raman lasers by virtue of improved pump absorption and relieved thermal loading.
基金supported by the National High Technology Research and Development Program of China(No.2013AA014201)the Tianjin Youth Science Foundation(No.13JCQNJC01800)
文摘A switchable dual-wavelength erbium-doped fiber laser(EDFL) with tunable wavelength is demonstrated. The ring cavity consists of two branches with a fiber Bragg grating(FBG) and a spherical-shape structure as fiber filters, respectively. By adjusting the variable optical attenuator(VOA), the laser can be switched between the single-wavelength mode and the dual-wavelength mode. The spherical-shape structure has good sensitivity to the temperature. When the temperature changes from 30 °C to 190 °C, the central wavelength of the EDFL generated by the branch of spherical-shape structure varies from 1 551.6 nm to 1 561.8 nm, which means that the wavelength interval is tunable.
