The poor contact and side reactions between Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)and lithium(Li)anode cause uneven Li plating and high interfacial impendence,which greatly hinder the practical application of LATP...The poor contact and side reactions between Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)and lithium(Li)anode cause uneven Li plating and high interfacial impendence,which greatly hinder the practical application of LATP in high-energy density solid-state Li metal batteries.In this work,a multifunctional ferroelectric BaTiO_(3)(BTO)/poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene)(P[VDF-TrFE-CTFE])composite interlayer(B-TERB)is constructed between LATP and Li metal anode,which not only suppresses the Li dendrite growth,but also improves the interfacial stability and maintains the intimate interfacial contact to significantly decrease the interfacial resistance by two orders of magnitude.The B-TERB interlayer generates a uniform electric field to induce a uniform and lateral Li deposition,and therefore avoids the side reactions between Li metal and LATP achieving excellent interface stability.As a result,the Li/LATP@B-TERB/Li symmetrical batteries can stably cycle for 1800 h at 0.2 mA cm^(-2)and 1000 h at 0.5 mA cm^(-2).The solid-state LiFePO_(4)/LATP@B-TERB/Li full batteries also exhibit excellent cycle performance for 250 cycles at 0.5 C and room temperature.This work proposes a novel strategy to design multifunctional ferroelectric interlayer between ceramic electrolytes and Li metal to enable stable room-temperature cycling performance.展开更多
As silicon photonics transitions from research to commercial deployment,packaging solutions that efficiently couple light into highly compact and functional sub-micrometer silicon waveguides are imperative but remain ...As silicon photonics transitions from research to commercial deployment,packaging solutions that efficiently couple light into highly compact and functional sub-micrometer silicon waveguides are imperative but remain challenging.The 220 nm silicon-on-insulator(SOI)platform,poised to enable large-scale integration,is the most widely adopted by foundries,resulting in established fabrication processes and extensive photonic component libraries.The development of a highly efficient,scalable,and broadband coupling scheme for this platform is therefore of paramount importance.Leveraging two-photon polymerization(TPP)and a deterministic free-form micro-optics design methodology based on the Fermat’s principle,this work demonstrates an ultraefficient and broadband 3-D coupler interface between standard SMF-28 single-mode fibers and silicon waveguides on the 220 nm SOI platform.The coupler achieves a low coupling loss of 0.8 dB for the fundamental TE mode,along with 1 dB bandwidth exceeding 180 nm.The broadband operation enables diverse bandwidthdriven applications ranging from communications to spectroscopy.Furthermore,the 3-D free-form coupler also enables large tolerance to fiber misalignments and manufacturing variability,thereby relaxing packaging requirements toward cost reduction capitalizing on standard electronic packaging process flows.展开更多
On-chip spectroscopic sensors have attracted increasing attention for portable and field-deployable chemical detection applications. So far, these sensors largely rely on benchtop tunable lasers for spectroscopic inte...On-chip spectroscopic sensors have attracted increasing attention for portable and field-deployable chemical detection applications. So far, these sensors largely rely on benchtop tunable lasers for spectroscopic interrogation. Large footprint and mechanical fragility of the sources, however, preclude compact sensing system integration. In this paper, we address the challenge through demonstrating, for the first time to our knowledge, a supercontinuum source integrated on-chip spectroscopic sensor, where we leverage nonlinear Ge_(22)Sb_(18)Se_(60) chalcogenide glass waveguides as a unified platform for both broadband supercontinuum generation and chemical detection. A home-built, palm-sized femtosecond laser centering at 1560 nm wavelength was used as the pumping source. Sensing capability of the system was validated through quantifying the optical absorption of chloroform solutions at 1695 nm. This work represents an important step towards realizing a miniaturized spectroscopic sensing system based on photonic chips.展开更多
Wide field-of-view(FOV)optics are essential components in many optical systems,with applications spanning imaging,display,sensing,and beam steering.Conventional refractive wide FOV optics often involve multiple stacke...Wide field-of-view(FOV)optics are essential components in many optical systems,with applications spanning imaging,display,sensing,and beam steering.Conventional refractive wide FOV optics often involve multiple stacked lenses,resulting in large size and weight as well as high cost.Metasurface lenses or metalenses promise a viable solution to realizing wide FOV optics without complex lens assembly.We review the various architectures of wide FOV metalenses,elucidate their fundamental operating principles and design trade-offs,and quantitatively evaluate and contrast their imaging performances.Emerging applications enabled by wide FOV metasurface optics are also discussed.展开更多
Photonic integrated circuits(PICs)have long been considered as disruptive platforms that revolutionize optics.Building on the mature industrial foundry infrastructure for electronic integrated circuit fabrication,the ...Photonic integrated circuits(PICs)have long been considered as disruptive platforms that revolutionize optics.Building on the mature industrial foundry infrastructure for electronic integrated circuit fabrication,the manufacturing of PICs has made remarkable progress.However,the packaging of PICs has often become a major barrier impeding their scalable deployment owing to their tight optical alignment tolerance,and hence,the requirement for specialty packaging instruments.Two-photon lithography(TPL),a laser direct-write three-dimensional(3-D)patterning technique with deep subwavelength resolution,has emerged as a promising solution for integrated photonics packaging.This study provides an overview of the technology,emphasizing the latest advances in TPL-enabled packaging schemes and their prospects for adoption in the mainstream photonic industry.展开更多
Integrated photonics is poised to become a mainstream solution for high-speed data communications and sensing in harsh radiation environments,such as outer space,high-energy physics facilities,nuclear power plants,and...Integrated photonics is poised to become a mainstream solution for high-speed data communications and sensing in harsh radiation environments,such as outer space,high-energy physics facilities,nuclear power plants,and test fusion reactors.Understanding the impact of radiation damage in optical materials and devices is thus a prerequisite to building radiation-hard photonic systems for these applications.In this paper,we report real-time,in situ analysis of radiation damage in integrated photonic devices.The devices,integrated with an optical fiber array package and a baseline-correction temperature sensor,can be remotely interrogated while exposed to ionizing radiation over a long period without compromising their structural and optical integrity.We also introduce a method to deconvolve the radiation damage responses from different constituent materials in a device.The approach was implemented to quantify gamma radiation damage and post-radiation relaxation behavior of SiO2-cladded SiC photonic devices.Our findings suggest that densification induced by Compton scattering displacement defects is the primary mechanism for the observed index change in SiC.Additionally,post-radiation relaxation in amorphous SiC does not restore the original pre-irradiated structural state of the material.Our results further point to the potential of realizing radiation-hard photonic device designs taking advantage of the opposite signs of radiation-induced index changes in SiC and SiO2.展开更多
Mechanically stretchable photonics provides a new geometric degree of freedom for photonic system design and foresees applications ranging from artificial skins to soft wearable electronics.Here we describe the design...Mechanically stretchable photonics provides a new geometric degree of freedom for photonic system design and foresees applications ranging from artificial skins to soft wearable electronics.Here we describe the design and experimental realization of the first single-mode stretchable photonic devices.These devices,made of chalcogenide glass and epoxy polymer materials,are monolithically integrated on elastomer substrates.To impart mechanical stretching capability to devices built using these intrinsically brittle materials,our design strategy involves local substrate stiffening to minimize shape deformation of critical photonic components,and interconnecting optical waveguides assuming a meandering Euler spiral geometry to mitigate radiative optical loss.Devices fabricated following such design can sustain 41%nominal tensile strain and 3000 stretching cycles without measurable degradation in optical performance.In addition,we present a rigorous analytical model to quantitatively predict stressoptical coupling behavior in waveguide devices of arbitrary geometry without using a single fitting parameter.展开更多
基金supported by National Natural Science Foundation of China(No.U2001220)Local Innovative Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01N111)+1 种基金Shenzhen All-Solid-State Lithium Battery Electrolyte Engineering Research Center(XMHT20200203006)Shenzhen Technical Plan Project(Nos.RCJC20200714114436091,JCYJ20180508152210821,and JCYJ20180508152135822).
文摘The poor contact and side reactions between Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)and lithium(Li)anode cause uneven Li plating and high interfacial impendence,which greatly hinder the practical application of LATP in high-energy density solid-state Li metal batteries.In this work,a multifunctional ferroelectric BaTiO_(3)(BTO)/poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene)(P[VDF-TrFE-CTFE])composite interlayer(B-TERB)is constructed between LATP and Li metal anode,which not only suppresses the Li dendrite growth,but also improves the interfacial stability and maintains the intimate interfacial contact to significantly decrease the interfacial resistance by two orders of magnitude.The B-TERB interlayer generates a uniform electric field to induce a uniform and lateral Li deposition,and therefore avoids the side reactions between Li metal and LATP achieving excellent interface stability.As a result,the Li/LATP@B-TERB/Li symmetrical batteries can stably cycle for 1800 h at 0.2 mA cm^(-2)and 1000 h at 0.5 mA cm^(-2).The solid-state LiFePO_(4)/LATP@B-TERB/Li full batteries also exhibit excellent cycle performance for 250 cycles at 0.5 C and room temperature.This work proposes a novel strategy to design multifunctional ferroelectric interlayer between ceramic electrolytes and Li metal to enable stable room-temperature cycling performance.
基金National Science Foundation(ITE-2236093,NSF ITE Convergence Accelerator)Ministry of Education-Singapore(International Postdoctoral Fellowship)。
文摘As silicon photonics transitions from research to commercial deployment,packaging solutions that efficiently couple light into highly compact and functional sub-micrometer silicon waveguides are imperative but remain challenging.The 220 nm silicon-on-insulator(SOI)platform,poised to enable large-scale integration,is the most widely adopted by foundries,resulting in established fabrication processes and extensive photonic component libraries.The development of a highly efficient,scalable,and broadband coupling scheme for this platform is therefore of paramount importance.Leveraging two-photon polymerization(TPP)and a deterministic free-form micro-optics design methodology based on the Fermat’s principle,this work demonstrates an ultraefficient and broadband 3-D coupler interface between standard SMF-28 single-mode fibers and silicon waveguides on the 220 nm SOI platform.The coupler achieves a low coupling loss of 0.8 dB for the fundamental TE mode,along with 1 dB bandwidth exceeding 180 nm.The broadband operation enables diverse bandwidthdriven applications ranging from communications to spectroscopy.Furthermore,the 3-D free-form coupler also enables large tolerance to fiber misalignments and manufacturing variability,thereby relaxing packaging requirements toward cost reduction capitalizing on standard electronic packaging process flows.
基金National Science Foundation(NSF)(6937070)Defense Threat Reduction Agency(DTRA)(HDTRA1-13-1-0001)+1 种基金National Natural Science Foundation of China(NSFC)(61475129)Natural Science Foundation of Fujian Province,China(2017J06016)
文摘On-chip spectroscopic sensors have attracted increasing attention for portable and field-deployable chemical detection applications. So far, these sensors largely rely on benchtop tunable lasers for spectroscopic interrogation. Large footprint and mechanical fragility of the sources, however, preclude compact sensing system integration. In this paper, we address the challenge through demonstrating, for the first time to our knowledge, a supercontinuum source integrated on-chip spectroscopic sensor, where we leverage nonlinear Ge_(22)Sb_(18)Se_(60) chalcogenide glass waveguides as a unified platform for both broadband supercontinuum generation and chemical detection. A home-built, palm-sized femtosecond laser centering at 1560 nm wavelength was used as the pumping source. Sensing capability of the system was validated through quantifying the optical absorption of chloroform solutions at 1695 nm. This work represents an important step towards realizing a miniaturized spectroscopic sensing system based on photonic chips.
基金Funding support was provided by the Defense Advanced Research Projects Agency,the Defense Sciences Office(DSO)Programs:EXTREME Optics and Imaging(EXTREME)under Agreement No.HR00111720029the Enhanced Night Vision in Eyeglass Form(ENVision)under Agreement No.HR001121S0013.
文摘Wide field-of-view(FOV)optics are essential components in many optical systems,with applications spanning imaging,display,sensing,and beam steering.Conventional refractive wide FOV optics often involve multiple stacked lenses,resulting in large size and weight as well as high cost.Metasurface lenses or metalenses promise a viable solution to realizing wide FOV optics without complex lens assembly.We review the various architectures of wide FOV metalenses,elucidate their fundamental operating principles and design trade-offs,and quantitatively evaluate and contrast their imaging performances.Emerging applications enabled by wide FOV metasurface optics are also discussed.
基金S.Y.and Q.D.acknowledge funding support from the National Key R&D Program of China 2021ZD0109904the Key Research Project of Zhejiang Lab No.2022PH0AC03.C.R.M.acknowledges the funding support provided by the Fulbright Program.
文摘Photonic integrated circuits(PICs)have long been considered as disruptive platforms that revolutionize optics.Building on the mature industrial foundry infrastructure for electronic integrated circuit fabrication,the manufacturing of PICs has made remarkable progress.However,the packaging of PICs has often become a major barrier impeding their scalable deployment owing to their tight optical alignment tolerance,and hence,the requirement for specialty packaging instruments.Two-photon lithography(TPL),a laser direct-write three-dimensional(3-D)patterning technique with deep subwavelength resolution,has emerged as a promising solution for integrated photonics packaging.This study provides an overview of the technology,emphasizing the latest advances in TPL-enabled packaging schemes and their prospects for adoption in the mainstream photonic industry.
文摘Integrated photonics is poised to become a mainstream solution for high-speed data communications and sensing in harsh radiation environments,such as outer space,high-energy physics facilities,nuclear power plants,and test fusion reactors.Understanding the impact of radiation damage in optical materials and devices is thus a prerequisite to building radiation-hard photonic systems for these applications.In this paper,we report real-time,in situ analysis of radiation damage in integrated photonic devices.The devices,integrated with an optical fiber array package and a baseline-correction temperature sensor,can be remotely interrogated while exposed to ionizing radiation over a long period without compromising their structural and optical integrity.We also introduce a method to deconvolve the radiation damage responses from different constituent materials in a device.The approach was implemented to quantify gamma radiation damage and post-radiation relaxation behavior of SiO2-cladded SiC photonic devices.Our findings suggest that densification induced by Compton scattering displacement defects is the primary mechanism for the observed index change in SiC.Additionally,post-radiation relaxation in amorphous SiC does not restore the original pre-irradiated structural state of the material.Our results further point to the potential of realizing radiation-hard photonic device designs taking advantage of the opposite signs of radiation-induced index changes in SiC and SiO2.
基金support is provided by the National Science Foundation under award numbers 1453218,1506605,and 1351875facility support by the MIT Microsystems Technology Laboratories and the Harvard University Center for Nanoscale Systemssupported by the National Science Foundation under award 0335765.
文摘Mechanically stretchable photonics provides a new geometric degree of freedom for photonic system design and foresees applications ranging from artificial skins to soft wearable electronics.Here we describe the design and experimental realization of the first single-mode stretchable photonic devices.These devices,made of chalcogenide glass and epoxy polymer materials,are monolithically integrated on elastomer substrates.To impart mechanical stretching capability to devices built using these intrinsically brittle materials,our design strategy involves local substrate stiffening to minimize shape deformation of critical photonic components,and interconnecting optical waveguides assuming a meandering Euler spiral geometry to mitigate radiative optical loss.Devices fabricated following such design can sustain 41%nominal tensile strain and 3000 stretching cycles without measurable degradation in optical performance.In addition,we present a rigorous analytical model to quantitatively predict stressoptical coupling behavior in waveguide devices of arbitrary geometry without using a single fitting parameter.
