In many application scenarios,silicon(Si)photonics favors the integration of Ⅲ-Ⅴ gain material onto Si substrate to real-ize the on-chip light source.In addition to the current popular integration approaches of Ⅲ-...In many application scenarios,silicon(Si)photonics favors the integration of Ⅲ-Ⅴ gain material onto Si substrate to real-ize the on-chip light source.In addition to the current popular integration approaches of Ⅲ-Ⅴ-on-Si wafer bonding or dir-ect heteroepitaxial growth,a newly emerged promising solution of epitaxial regrowth on bonded substrate has attracted a lot of interests.High-quality Ⅲ-Ⅴ material realization and successful laser demonstrations show its great potential to be a promising integration platform for low-cost,high-integration density and highly scalable active-passive photonic integra-tion on Si.This paper reviews recent research work on this regrowth on bonded template platform including template de-velopments,regrown material characterizations and laser demonstrations.The potential advantages,opportunities and challenges of this approach are discussed.展开更多
We summarized the design, fabrication challenges and important technologies for multi-wavelength laser transmitting photonic integration. Technologies discussed include multi-wavelength laser arrays, monolithic integr...We summarized the design, fabrication challenges and important technologies for multi-wavelength laser transmitting photonic integration. Technologies discussed include multi-wavelength laser arrays, monolithic integration and modularizing coupling and packaging. Fabrication technique requirements have significantly declined with the rise of reconstruction-equivalent-chirp and second nanoimprint mask technologies. The monolithic integration problem between active and passive waveguides can be overcome with Butt-joint and InP array waveguide grating technologies. The dynamic characteristics of multi-factors will be simultaneously measured with multi-port analyzing modules. The performance of photonic integration chips is significantly improved with the autoecious factors compensation packaging technique.展开更多
Due to the indirect bandgap nature,the widely used silicon CMOS is very inefficient at light emitting.The integration of silicon lasers is deemed as the‘Mount Everest’for the full take-up of Si photonics.The major c...Due to the indirect bandgap nature,the widely used silicon CMOS is very inefficient at light emitting.The integration of silicon lasers is deemed as the‘Mount Everest’for the full take-up of Si photonics.The major challenge has been the materials dissimilarity caused impaired device performance.We present a brief overview of the recent advances of integratedⅢ-Ⅴlaser on Si.We will then focus on the heterogeneous direct/adhesive bonding enabling methods and associated light coupling structures.A selected review of recent representative novel heterogeneously integrated Si lasers for emerging applications like spectroscopy,sensing,metrology and microwave photonics will be presented,including DFB laser array,ultra-dense comb lasers and nanolasers.Finally,the challenges and opportunities of heterogeneous integration approach are discussed.展开更多
Growing semiconductor laser sources on silicon is a crucial but challenging technology for developing photonic integrated circuits(PICs).InAs/GaAs quantum dot(Qdot)lasers have successfully circumvented the mismatch pr...Growing semiconductor laser sources on silicon is a crucial but challenging technology for developing photonic integrated circuits(PICs).InAs/GaAs quantum dot(Qdot)lasers have successfully circumvented the mismatch problem betweenⅢ–Ⅴmaterials and Ge or Si,and have demonstrated efficient laser emission.In this paper,we review dynamical characteristics of Qdot lasers epitaxially grown on Ge or Si,in comparison with those of Qdot lasers on native GaAs substrate.We discuss properties of linewidth broadening factor,laser noise and its sensitivity to optical feedback,intensity modulation,as well as mode locking operation.The investigation of these dynamical characteristics is beneficial for guiding the design of PICs in optical communications and optical computations.展开更多
Silicon-based photonic integration has attracted the interest of semiconductor scientists because it has high luminous efficiency and electron mobility.Breakthroughs have been made in silicon-based integrated lasers o...Silicon-based photonic integration has attracted the interest of semiconductor scientists because it has high luminous efficiency and electron mobility.Breakthroughs have been made in silicon-based integrated lasers over the past few decades.Here we review three main methods of integration ofⅢ–Ⅴ materials on Si,namely direct growth,bonding,and selectivearea hetero-epitaxy.TheⅢ–Ⅴmaterials we introduced mainly include materials such as GaAs and InP.The lasers are mainly lasers of related communication bands.We also introduced the advantages and challenges of the three methods.展开更多
Monolithic integration of Ⅲ-Ⅴ lasers with small footprint, good coherence, and low power consumption based on a CMOS-compatible Si substrate have been known as an efficient route towards high-density optical interco...Monolithic integration of Ⅲ-Ⅴ lasers with small footprint, good coherence, and low power consumption based on a CMOS-compatible Si substrate have been known as an efficient route towards high-density optical interconnects in the photonic integrated circuits. However, the material dissimilarities between Si and Ⅲ-Ⅴ materials limit the performance of monolithic microlasers. Here, under the pumping condition of a continuous-wave 632.8 nm He–Ne gas laser at room temperature, we achieved an InAs/GaAs quantum dot photonic crystal bandedge laser, which is directly grown on an on-axis Si(001) substrate, which provides a feasible route towards a low-cost and large-scale integration method for light sources on the Si platform.展开更多
Integrated photonics is attracting considerable attention and has found many applications in both classical and quantum optics,fulfilling the requirements for the ever-growing complexity in modern optical experiments ...Integrated photonics is attracting considerable attention and has found many applications in both classical and quantum optics,fulfilling the requirements for the ever-growing complexity in modern optical experiments and big data communication.Femtosecond(fs)laser direct writing(FLDW)is an acknowledged technique for producing waveguides(WGs)in transparent glass that have been used to construct complex integrated photonic devices.FLDW possesses unique features,such as three-dimensional fabrication geometry,rapid prototyping,and single step fabrication,which are important for integrated communication devices and quantum photonic and astrophotonic technologies.To fully take advantage of FLDW,considerable efforts have been made to produce WGs over a large depth with low propagation loss,coupling loss,bend loss,and highly symmetrical mode field.We summarize the improved techniques as well as the mechanisms for writing high-performance WGs with controllable morphology of cross-section,highly symmetrical mode field,low loss,and high processing uniformity and efficiency,and discuss the recent progress of WGs in photonic integrated devices for communication,topological physics,quantum information processing,and astrophotonics.Prospective challenges and future research directions in this field are also pointed out.展开更多
The importance of integrated quantum photonics in the telecom band is based on the possibility of interfacing with the optical network infrastructure that was developed for classical communications.In this framework,f...The importance of integrated quantum photonics in the telecom band is based on the possibility of interfacing with the optical network infrastructure that was developed for classical communications.In this framework,femtosecond laser-written integrated photonic circuits,which have already been assessed for use in quantum information experiments in the 800-nm wavelength range,have great potential.In fact,these circuits,being written in glass,can be perfectly mode-matched at telecom wavelength to the in/out coupling fibers,which is a key requirement for a low-loss processing node in future quantum optical networks.In addition,for several applications,quantum photonic devices must be dynamically reconfigurable.Here,we experimentally demonstrate the high performance of femtosecond laser-written photonic circuits for use in quantum experiments in the telecom band,and we demonstrate the use of thermal shifters,which were also fabricated using the same femtosecond laser,to accurately tune such circuits.State-of-the-art manipulation of single-and two-photon states is demonstrated,with fringe visibilities greater than 95%.The results of this work open the way to the realization of reconfigurable quantum photonic circuits based on this technological platform.展开更多
超导单光子探测技术能够实现光子量级极微弱光接收,是深空探测的关键技术之一,然而光子概率分布产生的脉冲抖动效应造成通信、测距性能恶化。对此,设计了基于脉冲位置调制(pulse position modulation,PPM)调制的单光子激光通信测距一体...超导单光子探测技术能够实现光子量级极微弱光接收,是深空探测的关键技术之一,然而光子概率分布产生的脉冲抖动效应造成通信、测距性能恶化。对此,设计了基于脉冲位置调制(pulse position modulation,PPM)调制的单光子激光通信测距一体化系统。根据光子分布特性,提出了脉冲宽度压缩的PPM新波形,降低了脉冲抖动效应对通信可靠性、测距精度的影响。同时,研制了星载端与地面端原理样机,搭建了双向通信与同步转发测距试验验证平台。试验验证结果表明,同等接收功率(-53.2 dBm)条件下,采用1/4脉宽压缩比时,通信接收误码率从4.7×10^(-4)降至5×10^(-10),测距精度从23.61 cm提高至0.91 cm,实现了高可靠通信传输与高精度距离测量。展开更多
Semiconductor mode-locked lasers(MLLs)can provide coherent optical frequency combs(OFCs)with high repetition rates and output power,which have been recognized as potential multi-wavelength sources used in optical comm...Semiconductor mode-locked lasers(MLLs)can provide coherent optical frequency combs(OFCs)with high repetition rates and output power,which have been recognized as potential multi-wavelength sources used in optical communication field due to their compactness,high-efficiency,and low-cost properties.In this article,we have reviewed recent development of semiconductor MLL-based frequency comb generation.Different approaches of semiconductor MLLs for OFC generation are synoptically summarized based on various material platforms.The representative progress of III-V semiconductor MLLs on III-V platform and especially on Si substrates is both discussed for the applications in integrated silicon photonics.展开更多
A compact multi-wavelength hybrid-integrated directly-modulated distributed-feedback laser(DML)transmitter optical sub-assembly(TOSA)has been achieved in our laboratory.The 8-channel distributed feedback(DFB)lasers ar...A compact multi-wavelength hybrid-integrated directly-modulated distributed-feedback laser(DML)transmitter optical sub-assembly(TOSA)has been achieved in our laboratory.The 8-channel distributed feedback(DFB)lasers are monolithically integrated based on the reconstruction-equivalent-chirp(REC)technology.With the high-density and high-speed packaging technique,the laser array and a multi-mode interference(MMI)multiplexer are assembled in the TOSA.The channel spacing of the TOSA is 200 GHz between adjacent lasers.It meets the 8 9 12.5 Gb/s operation demand and gives rather low channel crosstalk of less than-25 dB.This compact TOSA is of effective cost and shows good stability for mass production,which is expected to improve the performance of devices in access networks,data centers and supercomputing.展开更多
The continuing trend of exponential growth in data communications and processing are driving the need for large-scale heterogeneous integration.Similar to the trend we have observed in electronic integrated circuit de...The continuing trend of exponential growth in data communications and processing are driving the need for large-scale heterogeneous integration.Similar to the trend we have observed in electronic integrated circuit development,we are witnessing a growing trend in 3D photonic integrated circuits(PICs)development in addition to that in 2D PICs.There are two main methods for fabricating 3D PICs.The first method,which utilizes ultrafast laser inscription(ULI),offers freeform shaping of waveguides in arbitrary contours and formations.The second method,which utilizes multilayer stacking and coupling of planar PICs,exploits relatively mature 2D PIC fabrication processes applied to each layer sequentially.Both the fabrication methods for 3D PICs have advantages and disadvantages such that certain applications may favor one method over the other.However,a joining of 2D PICs with 3D PICs can help develop integrated microsystems with new functionalities such as non-mechanical beam steering,spacedivision multiplexing(SDM),programmable arbitrary beam shaping,and photonic signal processing.We discuss examples of 3D PICs and 2D/3D integrated PICs in two applications:SDM via orbital-angular-momentum(OAM)multiplexing/demultiplexing and optical beam steering using optical phased arrays.Although a 2D PIC by itself can function as an OAM multiplexer or demultiplexer,it has limitations in supporting both polarizations.Alternatively,a 3D PIC fabricated by ULI can easily support both polarizations with low propagation loss.A combination of a 3D PIC and a 2D PIC designed and fabricated for OAM applications has successfully multiplexed and demultiplexed 15 OAM states to demonstrate polarization-diversified SDM coherent optical communications using multiple OAM states.Coherent excitation of multi-ring OAM states can allow highly scalable SDM utilizing Laguerre–Gaussian modes or linearly polarized(LP)modes.The preliminary fabrication of multi-ring OAM multiplexers and demultiplexers using the multilayer 3D PIC method and the ULI 3D PIC method has also been pursued.Large-scale(for example,16×16 optical phased array)3D PICs fabricated with the ULI technique have been demonstrated.Through these examples,we show that heterogeneous 2D/3D photonic integration retains the advantages of 2D PICs and 3D waveguides,which can potentially benefit many other applications.展开更多
Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully...Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully realize integrated silicon electronic and photonic integrated circuits has greatly pushed the effort of realizing high performance on-chip lasers and amplifiers moving forward.Several approaches have been proposed and demonstrated to address this issue.In this paper,a brief overview of recent progress of the high-performance lasers and amplifiers on Si based on different technology is presented.Representative device demonstrations,including ultra-narrow linewidthⅢ-Ⅴ/Si lasers,fully integratedⅢ-Ⅴ/Si/Si3N4 lasers,high-channel count mode locked quantum dot(QD)lasers,and high gain QD amplifiers will be covered.展开更多
Let there be light-to change the world we want to be!Over the past several decades,and ever since the birth of the first laser,mankind has witnessed the development of the science of light,as light-based technologies ...Let there be light-to change the world we want to be!Over the past several decades,and ever since the birth of the first laser,mankind has witnessed the development of the science of light,as light-based technologies have revolutionarily changed our lives.Needless to say,photonics has now penetrated into many aspects of science and technology,turning into an important and dynamically changing field of increasing interdisciplinary interest.In this inaugural issue of eLight,we highlight a few emerging trends in photonics that we think are likely to have major impact at least in the upcoming decade,spanning from integrated quantum photonics and quantum computing,through topological/non-Hermitian photonics and topological insulator lasers,to AI-empowered nanophotonics and photonic machine learning.This Perspective is by no means an attempt to summarize all the latest advances in photonics,yet we wish our subjective vision could fuel inspiration and foster excitement in scientific research especially for young researchers who love the science of light.展开更多
文摘In many application scenarios,silicon(Si)photonics favors the integration of Ⅲ-Ⅴ gain material onto Si substrate to real-ize the on-chip light source.In addition to the current popular integration approaches of Ⅲ-Ⅴ-on-Si wafer bonding or dir-ect heteroepitaxial growth,a newly emerged promising solution of epitaxial regrowth on bonded substrate has attracted a lot of interests.High-quality Ⅲ-Ⅴ material realization and successful laser demonstrations show its great potential to be a promising integration platform for low-cost,high-integration density and highly scalable active-passive photonic integra-tion on Si.This paper reviews recent research work on this regrowth on bonded template platform including template de-velopments,regrown material characterizations and laser demonstrations.The potential advantages,opportunities and challenges of this approach are discussed.
基金the National High-Tech Research & Development Program of China (2011AA0103)
文摘We summarized the design, fabrication challenges and important technologies for multi-wavelength laser transmitting photonic integration. Technologies discussed include multi-wavelength laser arrays, monolithic integration and modularizing coupling and packaging. Fabrication technique requirements have significantly declined with the rise of reconstruction-equivalent-chirp and second nanoimprint mask technologies. The monolithic integration problem between active and passive waveguides can be overcome with Butt-joint and InP array waveguide grating technologies. The dynamic characteristics of multi-factors will be simultaneously measured with multi-port analyzing modules. The performance of photonic integration chips is significantly improved with the autoecious factors compensation packaging technique.
基金supported by Natural Science Foundation of China (NSFC) under Grant 61805137Natural Science Foundation of Shanghai under Grant 19ZR1475400+1 种基金Shanghai Sailing Program under Grant 18YF1411900the Open Project Program of Wuhan National Laboratory for Optoelectronics No. 2018WNLOKF012
文摘Due to the indirect bandgap nature,the widely used silicon CMOS is very inefficient at light emitting.The integration of silicon lasers is deemed as the‘Mount Everest’for the full take-up of Si photonics.The major challenge has been the materials dissimilarity caused impaired device performance.We present a brief overview of the recent advances of integratedⅢ-Ⅴlaser on Si.We will then focus on the heterogeneous direct/adhesive bonding enabling methods and associated light coupling structures.A selected review of recent representative novel heterogeneously integrated Si lasers for emerging applications like spectroscopy,sensing,metrology and microwave photonics will be presented,including DFB laser array,ultra-dense comb lasers and nanolasers.Finally,the challenges and opportunities of heterogeneous integration approach are discussed.
基金supported by National Natural Science Foundation of China (No. 61804095)by Shanghai Pujiang Program (No. 17PJ1406500)
文摘Growing semiconductor laser sources on silicon is a crucial but challenging technology for developing photonic integrated circuits(PICs).InAs/GaAs quantum dot(Qdot)lasers have successfully circumvented the mismatch problem betweenⅢ–Ⅴmaterials and Ge or Si,and have demonstrated efficient laser emission.In this paper,we review dynamical characteristics of Qdot lasers epitaxially grown on Ge or Si,in comparison with those of Qdot lasers on native GaAs substrate.We discuss properties of linewidth broadening factor,laser noise and its sensitivity to optical feedback,intensity modulation,as well as mode locking operation.The investigation of these dynamical characteristics is beneficial for guiding the design of PICs in optical communications and optical computations.
基金supported by the National Key Technology R&D Program (Grant No. 2018YFA0209001)Frontier Science Research Project of CAS (Grant No. QYZDY-SSWJSC021)
文摘Silicon-based photonic integration has attracted the interest of semiconductor scientists because it has high luminous efficiency and electron mobility.Breakthroughs have been made in silicon-based integrated lasers over the past few decades.Here we review three main methods of integration ofⅢ–Ⅴ materials on Si,namely direct growth,bonding,and selectivearea hetero-epitaxy.TheⅢ–Ⅴmaterials we introduced mainly include materials such as GaAs and InP.The lasers are mainly lasers of related communication bands.We also introduced the advantages and challenges of the three methods.
基金This research was supported by the National Natural Science Foundation of China(No.62174144)Shenzhen Fundamental Research Fund(Nos.JCYJ20210324115605016 and JCYJ20210324120204011)+7 种基金Optical Communication Core Chip Research Platform,Shenzhen Key Laboratory Project(No.ZDSYS201603311644527)Longgang Key Laboratory Project(Nos.ZSYS2017003 and LGKCZSYS2018000015)Longgang Matching Support Fund(Nos.CXPTPT-2017-YJ-002 and 201617486)President's Fund(PF01000154)UK Engineering and Physical Sciences Research Council(EP/P006973/1 and National Epitaxy Facility)European project H2020-ICT-PICTURE(780930)Royal Academy of Engineering(RF201617/16/28)French government managed by ANR under the Investissements davenir ANR-10-IRT-05 and ANR-15-IDEX-02 and French RENATECH network.
文摘Monolithic integration of Ⅲ-Ⅴ lasers with small footprint, good coherence, and low power consumption based on a CMOS-compatible Si substrate have been known as an efficient route towards high-density optical interconnects in the photonic integrated circuits. However, the material dissimilarities between Si and Ⅲ-Ⅴ materials limit the performance of monolithic microlasers. Here, under the pumping condition of a continuous-wave 632.8 nm He–Ne gas laser at room temperature, we achieved an InAs/GaAs quantum dot photonic crystal bandedge laser, which is directly grown on an on-axis Si(001) substrate, which provides a feasible route towards a low-cost and large-scale integration method for light sources on the Si platform.
基金This work was financially supported by the National Key R&D Program of China(2020YFB1805900)the National Natural Science Foundation of China(U20A20211,51902286,61775192,61905215,and 51772270)Open Funds of the State Key Laboratory of High Field Laser Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,and the Fundamental Research Funds for the Central Universities.The authors declare no competing financial interest.
文摘Integrated photonics is attracting considerable attention and has found many applications in both classical and quantum optics,fulfilling the requirements for the ever-growing complexity in modern optical experiments and big data communication.Femtosecond(fs)laser direct writing(FLDW)is an acknowledged technique for producing waveguides(WGs)in transparent glass that have been used to construct complex integrated photonic devices.FLDW possesses unique features,such as three-dimensional fabrication geometry,rapid prototyping,and single step fabrication,which are important for integrated communication devices and quantum photonic and astrophotonic technologies.To fully take advantage of FLDW,considerable efforts have been made to produce WGs over a large depth with low propagation loss,coupling loss,bend loss,and highly symmetrical mode field.We summarize the improved techniques as well as the mechanisms for writing high-performance WGs with controllable morphology of cross-section,highly symmetrical mode field,low loss,and high processing uniformity and efficiency,and discuss the recent progress of WGs in photonic integrated devices for communication,topological physics,quantum information processing,and astrophotonics.Prospective challenges and future research directions in this field are also pointed out.
基金This work was supported by the ERC-Starting Grant 3D-QUEST(3DQuantum Integrated Optical Simulationgrant agreement no.307783,http://www.3dquest.eu)by the Marie Curie Initial Training Network PICQUE(Photonic Integrated Compound Quantum Encoding,grant agreement no.608062,funding Program:FP7-PEOPLE-2013-ITN,http://www.picque.eu).
文摘The importance of integrated quantum photonics in the telecom band is based on the possibility of interfacing with the optical network infrastructure that was developed for classical communications.In this framework,femtosecond laser-written integrated photonic circuits,which have already been assessed for use in quantum information experiments in the 800-nm wavelength range,have great potential.In fact,these circuits,being written in glass,can be perfectly mode-matched at telecom wavelength to the in/out coupling fibers,which is a key requirement for a low-loss processing node in future quantum optical networks.In addition,for several applications,quantum photonic devices must be dynamically reconfigurable.Here,we experimentally demonstrate the high performance of femtosecond laser-written photonic circuits for use in quantum experiments in the telecom band,and we demonstrate the use of thermal shifters,which were also fabricated using the same femtosecond laser,to accurately tune such circuits.State-of-the-art manipulation of single-and two-photon states is demonstrated,with fringe visibilities greater than 95%.The results of this work open the way to the realization of reconfigurable quantum photonic circuits based on this technological platform.
基金supported by the National Natural Science Foundation of China(61975230 and 62008308)the National Key Research and Development Program of China(2021YFB2800400)Ting Wang was supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2018011)。
文摘Semiconductor mode-locked lasers(MLLs)can provide coherent optical frequency combs(OFCs)with high repetition rates and output power,which have been recognized as potential multi-wavelength sources used in optical communication field due to their compactness,high-efficiency,and low-cost properties.In this article,we have reviewed recent development of semiconductor MLL-based frequency comb generation.Different approaches of semiconductor MLLs for OFC generation are synoptically summarized based on various material platforms.The representative progress of III-V semiconductor MLLs on III-V platform and especially on Si substrates is both discussed for the applications in integrated silicon photonics.
基金supported by the National High-Tech Research&Development Program of China(2011AA010303,2013AA014201,and 2011AA010305)the National Natural Sci-ence Foundation of China(61177080)
文摘A compact multi-wavelength hybrid-integrated directly-modulated distributed-feedback laser(DML)transmitter optical sub-assembly(TOSA)has been achieved in our laboratory.The 8-channel distributed feedback(DFB)lasers are monolithically integrated based on the reconstruction-equivalent-chirp(REC)technology.With the high-density and high-speed packaging technique,the laser array and a multi-mode interference(MMI)multiplexer are assembled in the TOSA.The channel spacing of the TOSA is 200 GHz between adjacent lasers.It meets the 8 9 12.5 Gb/s operation demand and gives rather low channel crosstalk of less than-25 dB.This compact TOSA is of effective cost and shows good stability for mass production,which is expected to improve the performance of devices in access networks,data centers and supercomputing.
基金The authors acknowledge support in part by DARPA DSO Inpho grant HR0011-11-1-0005,ONR EW grant N000141310158NSF NeTS grant 1302719.
文摘The continuing trend of exponential growth in data communications and processing are driving the need for large-scale heterogeneous integration.Similar to the trend we have observed in electronic integrated circuit development,we are witnessing a growing trend in 3D photonic integrated circuits(PICs)development in addition to that in 2D PICs.There are two main methods for fabricating 3D PICs.The first method,which utilizes ultrafast laser inscription(ULI),offers freeform shaping of waveguides in arbitrary contours and formations.The second method,which utilizes multilayer stacking and coupling of planar PICs,exploits relatively mature 2D PIC fabrication processes applied to each layer sequentially.Both the fabrication methods for 3D PICs have advantages and disadvantages such that certain applications may favor one method over the other.However,a joining of 2D PICs with 3D PICs can help develop integrated microsystems with new functionalities such as non-mechanical beam steering,spacedivision multiplexing(SDM),programmable arbitrary beam shaping,and photonic signal processing.We discuss examples of 3D PICs and 2D/3D integrated PICs in two applications:SDM via orbital-angular-momentum(OAM)multiplexing/demultiplexing and optical beam steering using optical phased arrays.Although a 2D PIC by itself can function as an OAM multiplexer or demultiplexer,it has limitations in supporting both polarizations.Alternatively,a 3D PIC fabricated by ULI can easily support both polarizations with low propagation loss.A combination of a 3D PIC and a 2D PIC designed and fabricated for OAM applications has successfully multiplexed and demultiplexed 15 OAM states to demonstrate polarization-diversified SDM coherent optical communications using multiple OAM states.Coherent excitation of multi-ring OAM states can allow highly scalable SDM utilizing Laguerre–Gaussian modes or linearly polarized(LP)modes.The preliminary fabrication of multi-ring OAM multiplexers and demultiplexers using the multilayer 3D PIC method and the ULI 3D PIC method has also been pursued.Large-scale(for example,16×16 optical phased array)3D PICs fabricated with the ULI technique have been demonstrated.Through these examples,we show that heterogeneous 2D/3D photonic integration retains the advantages of 2D PICs and 3D waveguides,which can potentially benefit many other applications.
文摘Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully realize integrated silicon electronic and photonic integrated circuits has greatly pushed the effort of realizing high performance on-chip lasers and amplifiers moving forward.Several approaches have been proposed and demonstrated to address this issue.In this paper,a brief overview of recent progress of the high-performance lasers and amplifiers on Si based on different technology is presented.Representative device demonstrations,including ultra-narrow linewidthⅢ-Ⅴ/Si lasers,fully integratedⅢ-Ⅴ/Si/Si3N4 lasers,high-channel count mode locked quantum dot(QD)lasers,and high gain QD amplifiers will be covered.
基金support from the National Key R&D Program of China under Grant(No.2017YFA0303800).MS acknowledges support from the Israel Science Foundation.
文摘Let there be light-to change the world we want to be!Over the past several decades,and ever since the birth of the first laser,mankind has witnessed the development of the science of light,as light-based technologies have revolutionarily changed our lives.Needless to say,photonics has now penetrated into many aspects of science and technology,turning into an important and dynamically changing field of increasing interdisciplinary interest.In this inaugural issue of eLight,we highlight a few emerging trends in photonics that we think are likely to have major impact at least in the upcoming decade,spanning from integrated quantum photonics and quantum computing,through topological/non-Hermitian photonics and topological insulator lasers,to AI-empowered nanophotonics and photonic machine learning.This Perspective is by no means an attempt to summarize all the latest advances in photonics,yet we wish our subjective vision could fuel inspiration and foster excitement in scientific research especially for young researchers who love the science of light.