The emergence of metalenses has impacted a wide variety of applications such as beam steering,imaging,depth sensing,and display projection.Optical distortion,an important metric among many optical design specification...The emergence of metalenses has impacted a wide variety of applications such as beam steering,imaging,depth sensing,and display projection.Optical distortion,an important metric among many optical design specifications,has however rarely been discussed in the context of meta-optics.Here,we present a generic approach for on-demand distortion engineering using compound metalenses.We show that the extra degrees of freedom afforded by a doublet metasurface architecture allow custom-tailored angle-dependent image height relations and hence distortion control while minimizing other monochromatic aberrations.Using this platform,we experimentally demonstrate a compound fisheye metalens with diffraction-limited performance across a wide field of view of 140°and a low barrel distortion of less than 2%,compared with up to 22%distortion in a reference metalens without compensation.The design strategy and compound metalens architecture presented herein are expected to broadly impact metasurface applications in consumer electronics,automotive and robotic sensing,medical imaging,and machine vision systems.展开更多
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
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
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
Allergen-specific immunotherapy(AIT)is the only treatment that addresses the root cause of immunoglobulin E(IgE)-mediated allergies,but conventional methods face challenges with treatment duration,patient compliance,a...Allergen-specific immunotherapy(AIT)is the only treatment that addresses the root cause of immunoglobulin E(IgE)-mediated allergies,but conventional methods face challenges with treatment duration,patient compliance,and adverse effects.In this study,we propose intratonsillar immunotherapy(ITIT)as a new effective and safer route for AIT.Prior to clinical trials,we analyzed tonsil samples from human subjects to assess immune responses,measuring interleukin-4(IL-4),IL-21,total IgE(tIgE),and allergen-specific IgE concentrations using ELISA and BioIC.Our results indicated that tonsils contained higher levels of allergen-specific IgE compared to peripheral blood.In the clinical phase,120 allergic rhinitis(AR)patients were treated with either 3 intratonsillar allergen injections over 2 months or conventional subcutaneous immunotherapy(SCIT)over 1 year.ITIT demonstrated superior and faster symptom relief,especially in younger patients,while requiring markedly fewer doses and injections than SCIT.Immunological analysis revealed reduced eosinophil counts,increased regulatory T(T_(reg))and follicular regulatory T(T_(FR))cell levels,and a favorable shift in cytokine profiles.Adverse events were minimal,and the treatment showed high patient compliance.These findings suggest that ITIT could provide an effective,safer,and more convenient alternative to AIT.展开更多
Wide field of view and light weight optics are critical for advanced eyewear,with applications in augmented/virtual reality and night vision.Conventional refractive lenses are often stacked to correct aberrations at a...Wide field of view and light weight optics are critical for advanced eyewear,with applications in augmented/virtual reality and night vision.Conventional refractive lenses are often stacked to correct aberrations at a wide field of view,leading to limited performance and increased size and weight.In particular,simultaneously achieving a wide field of view and large aperture for light collection is desirable but challenging to realize in a compact form-factor.Here,we demonstrate a wide field of view(greater than 60°)meta-optic doublet eyepiece with an entrance aperture of 2.1 cm.At the design wavelength of 633 nm,the meta-optic doublet achieves comparable performance to a refractive lens-based eyepiece system.This meta-doublet eyepiece illustrates the potential for meta-optics to play an important role in the development of high-quality monochrome near-eye displays and night vision systems.展开更多
Integrated photonics,where optical components are fabricated on a chip-scale platform leveraging standard microfabrication technologies,has transformed telecommunications and data communications,quantum optics,and mol...Integrated photonics,where optical components are fabricated on a chip-scale platform leveraging standard microfabrication technologies,has transformed telecommunications and data communications,quantum optics,and molecular sensing.Optical spectrometry is yet another field that integrated photonics is poised to revolutionize.Unlike traditional bulky,costly benchtop spectrometers,integrated photonics promises miniaturized,rugged,and low-cost spectrometer-on-a-chip modules with broad application prospects ranging from communications to medical imaging.In this review,we survey the various designs of integrated photonic spectrometers through the lens of their underlying operating principles,aiming to reveal quantitative performance scaling laws that transcend specific implementations.This approach enables a general,physically grounded comparison of spectrometer capabilities without being bogged down by device-level details.We further provide guidance on selecting appropriate spectrometer architectures for different applications,taking into account not only their reported advantages but also the practical limitations and implementation challenges.展开更多
Oxide solid-state electrolytes(OSEs)with high ionic conductivity,wide electrochemical window and inherent safety are critical to achieve high-energy-density and safe performance of solid-state batteries(SSBs).However,...Oxide solid-state electrolytes(OSEs)with high ionic conductivity,wide electrochemical window and inherent safety are critical to achieve high-energy-density and safe performance of solid-state batteries(SSBs).However,the large interfacial impedance and severe side reactions between OSEs and electrodes remain challenging for ion transport in SSBs,which is attributed to the poor physical contact and chemical compatibility between OSEs and electrode materials.In this review,the recent research on solid-state interfaces in SSBs is summarized and dis-cussed.These strategies can be categorized into interfacial structure design and interfacial modifications.Structure designs,including constructing architectural Li anode,three-dimension(3D)structure OSEs and inte-grated cathode can significantly increase the effective contact area between electrodes and OSEs to facilitate the interfacial ion transport.The interfacial modifications are utilized to improve the wettability of OSEs for lithium metal anode,enhance the interfacial ion transport,and stabilize the OSEs/electrodes interface.Interface archi-tecture is crucial to enhance structural stability and reduce interface impedance for advanced oxide-based SSBs.At last,the future research direction of interfacial modification in SSBs is prospected.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
Optical phase shifters constitute the fundamental building blocks that enableprogrammable photonic integrated circuits (PICs)—the cornerstone of on-chipclassical and quantum optical technologies [1, 2]. Thus far, car...Optical phase shifters constitute the fundamental building blocks that enableprogrammable photonic integrated circuits (PICs)—the cornerstone of on-chipclassical and quantum optical technologies [1, 2]. Thus far, carrier modulation andthermo-optical effect are the chosen phenomena for ultrafast and low-loss phaseshifters, respectively;however, the state and information they carry are lost once thepower is turned off—they are volatile. The volatility not only compromises energyefficiency due to their demand for constant power supply, but also precludes themfrom emerging applications such as in-memory computing. To circumvent thislimitation, we introduce a phase shifting mechanism that exploits the nonvolatilerefractive index modulation upon structural phase transition of Sb2Se3, a bi-statetransparent phase change material (PCM). A zero-static power and electrically-drivenphase shifter is realized on a CMOS-backend silicon-on-insulator platform, featuringrecord phase modulation up to 0.09 π/μm and a low insertion loss of 0.3 dB/π, whichcan be further improved upon streamlined design. Furthermore, we demonstratephase and extinction ratio trimming of ring resonators and pioneer a one-step partialamorphization scheme to enhance speed and energy efficiency of PCM devices. Adiverse cohort of programmable photonic devices is demonstrated based on theultra-compact PCM phase shifter.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
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
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funding support provided by the Defense Advanced Research Projects Agency Defense Sciences Office Program: Enhanced Night Vision in Eyeglass Form (ENVision)
文摘The emergence of metalenses has impacted a wide variety of applications such as beam steering,imaging,depth sensing,and display projection.Optical distortion,an important metric among many optical design specifications,has however rarely been discussed in the context of meta-optics.Here,we present a generic approach for on-demand distortion engineering using compound metalenses.We show that the extra degrees of freedom afforded by a doublet metasurface architecture allow custom-tailored angle-dependent image height relations and hence distortion control while minimizing other monochromatic aberrations.Using this platform,we experimentally demonstrate a compound fisheye metalens with diffraction-limited performance across a wide field of view of 140°and a low barrel distortion of less than 2%,compared with up to 22%distortion in a reference metalens without compensation.The design strategy and compound metalens architecture presented herein are expected to broadly impact metasurface applications in consumer electronics,automotive and robotic sensing,medical imaging,and machine vision systems.
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(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supported by grants from the National Key Research and Development Program of China(NKRD,no.2023YFC2507905 to Y.X.)the National Natural Science Foundation of China(NSFC,nos.82271134,82071017,and 81770986 to Y.X.+1 种基金no.82201250 to L.T.)the Fundamental Research Funds for the Central Universities(no.2042022kf1113 to Y.X.).
文摘Allergen-specific immunotherapy(AIT)is the only treatment that addresses the root cause of immunoglobulin E(IgE)-mediated allergies,but conventional methods face challenges with treatment duration,patient compliance,and adverse effects.In this study,we propose intratonsillar immunotherapy(ITIT)as a new effective and safer route for AIT.Prior to clinical trials,we analyzed tonsil samples from human subjects to assess immune responses,measuring interleukin-4(IL-4),IL-21,total IgE(tIgE),and allergen-specific IgE concentrations using ELISA and BioIC.Our results indicated that tonsils contained higher levels of allergen-specific IgE compared to peripheral blood.In the clinical phase,120 allergic rhinitis(AR)patients were treated with either 3 intratonsillar allergen injections over 2 months or conventional subcutaneous immunotherapy(SCIT)over 1 year.ITIT demonstrated superior and faster symptom relief,especially in younger patients,while requiring markedly fewer doses and injections than SCIT.Immunological analysis revealed reduced eosinophil counts,increased regulatory T(T_(reg))and follicular regulatory T(T_(FR))cell levels,and a favorable shift in cytokine profiles.Adverse events were minimal,and the treatment showed high patient compliance.These findings suggest that ITIT could provide an effective,safer,and more convenient alternative to AIT.
基金supported by the DARPA-ENVision programPart of this work was conducted at the Washington Nanofabrication Facility/Molecular Analysis Facility,a National Nanotechnology Coordinated Infrastructure(NNCI)site at the University of Washington with partial support from the National Science Foundation via awards NNCI-1542101 and NNCI-2025489。
文摘Wide field of view and light weight optics are critical for advanced eyewear,with applications in augmented/virtual reality and night vision.Conventional refractive lenses are often stacked to correct aberrations at a wide field of view,leading to limited performance and increased size and weight.In particular,simultaneously achieving a wide field of view and large aperture for light collection is desirable but challenging to realize in a compact form-factor.Here,we demonstrate a wide field of view(greater than 60°)meta-optic doublet eyepiece with an entrance aperture of 2.1 cm.At the design wavelength of 633 nm,the meta-optic doublet achieves comparable performance to a refractive lens-based eyepiece system.This meta-doublet eyepiece illustrates the potential for meta-optics to play an important role in the development of high-quality monochrome near-eye displays and night vision systems.
基金funding support provided by the NASA STTR contract 80NSSC23CA018NSF Award 2122581+1 种基金US Army Research Office through the Institute for Soldier Nanotechnologies Award W911NF-23-2-0121Simons Foundation through the Simons Collaboration on Extreme Wave Phenomena Based on Symmetries.
文摘Integrated photonics,where optical components are fabricated on a chip-scale platform leveraging standard microfabrication technologies,has transformed telecommunications and data communications,quantum optics,and molecular sensing.Optical spectrometry is yet another field that integrated photonics is poised to revolutionize.Unlike traditional bulky,costly benchtop spectrometers,integrated photonics promises miniaturized,rugged,and low-cost spectrometer-on-a-chip modules with broad application prospects ranging from communications to medical imaging.In this review,we survey the various designs of integrated photonic spectrometers through the lens of their underlying operating principles,aiming to reveal quantitative performance scaling laws that transcend specific implementations.This approach enables a general,physically grounded comparison of spectrometer capabilities without being bogged down by device-level details.We further provide guidance on selecting appropriate spectrometer architectures for different applications,taking into account not only their reported advantages but also the practical limitations and implementation challenges.
基金supported by the National Key Research and Development Program of China(2021YFF0500600)National Natural Science Foundation of China(No.U2001220 and 52203298)+2 种基金National Science Fund for Distinguished Young Scholars(No.52325206)Shenzhen Technical Plan Project(Nos.RCJC20200714114436091,JCYJ2022053-0143012027,JCYJ20220818101003008 and JCYJ20220818101-003007)Tsinghua Shenzhen International Graduate School-Shenzhen Pengrui Young Faculty Program of Shenzhen Pengrui Foundation(No.SZPR2023006).
文摘Oxide solid-state electrolytes(OSEs)with high ionic conductivity,wide electrochemical window and inherent safety are critical to achieve high-energy-density and safe performance of solid-state batteries(SSBs).However,the large interfacial impedance and severe side reactions between OSEs and electrodes remain challenging for ion transport in SSBs,which is attributed to the poor physical contact and chemical compatibility between OSEs and electrode materials.In this review,the recent research on solid-state interfaces in SSBs is summarized and dis-cussed.These strategies can be categorized into interfacial structure design and interfacial modifications.Structure designs,including constructing architectural Li anode,three-dimension(3D)structure OSEs and inte-grated cathode can significantly increase the effective contact area between electrodes and OSEs to facilitate the interfacial ion transport.The interfacial modifications are utilized to improve the wettability of OSEs for lithium metal anode,enhance the interfacial ion transport,and stabilize the OSEs/electrodes interface.Interface archi-tecture is crucial to enhance structural stability and reduce interface impedance for advanced oxide-based SSBs.At last,the future research direction of interfacial modification in SSBs is prospected.
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supported by the DARPA Young Faculty Award Program under Grant Number D18AP00070the Assistant Secretary of Defense for Research and Engineering under Air Force Contract No.FA8702-15-D-0001,and Draper Laboratory。
文摘Optical phase shifters constitute the fundamental building blocks that enableprogrammable photonic integrated circuits (PICs)—the cornerstone of on-chipclassical and quantum optical technologies [1, 2]. Thus far, carrier modulation andthermo-optical effect are the chosen phenomena for ultrafast and low-loss phaseshifters, respectively;however, the state and information they carry are lost once thepower is turned off—they are volatile. The volatility not only compromises energyefficiency due to their demand for constant power supply, but also precludes themfrom emerging applications such as in-memory computing. To circumvent thislimitation, we introduce a phase shifting mechanism that exploits the nonvolatilerefractive index modulation upon structural phase transition of Sb2Se3, a bi-statetransparent phase change material (PCM). A zero-static power and electrically-drivenphase shifter is realized on a CMOS-backend silicon-on-insulator platform, featuringrecord phase modulation up to 0.09 π/μm and a low insertion loss of 0.3 dB/π, whichcan be further improved upon streamlined design. Furthermore, we demonstratephase and extinction ratio trimming of ring resonators and pioneer a one-step partialamorphization scheme to enhance speed and energy efficiency of PCM devices. Adiverse cohort of programmable photonic devices is demonstrated based on theultra-compact PCM phase shifter.
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.
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.
