The development of two-dimensional(2D)semiconductors has attracted widespread attentions in the scientific community and industry due to their ultra-thin thickness,unique structure,excellent optoelectronic properties ...The development of two-dimensional(2D)semiconductors has attracted widespread attentions in the scientific community and industry due to their ultra-thin thickness,unique structure,excellent optoelectronic properties and novel physics.The excellent flexibility and outstanding mechanical strength of 2D semiconductors provide opportunities for fabricated strain-sensitive devices and utilized strain tuning their electronic and optic–electric performance.The strain-engineered one-dimensional materials have been well investigated,while there is a long way to go for 2D semiconductors.In this review,starting with the fundamental theories of piezoelectric and piezoresistive effect resulted by strain,following we reviewed the recent simulation works of strain engineering in novel 2D semiconductors,such as Janus 2D and 2D-Xene structures.Moreover,recent advances in experimental observation of strain tuning PL spectra and transport behavior of 2D semiconductors are summarized.Furthermore,the applications of strain-engineered 2D semiconductors in sensors,photodetectors and nanogenerators are also highlighted.At last,we in-depth discussed future research directions of strain-engineered 2D semiconductor and related electronics and optoelectronics device applications.展开更多
We summarize our work of the optoelectronic devices based on Germanium-tin (GeSn) alloys assisted with the Si3N4liner stressor in mid-infrared (MIR) domains. The device characteristics are thoroughly analyzed by t...We summarize our work of the optoelectronic devices based on Germanium-tin (GeSn) alloys assisted with the Si3N4liner stressor in mid-infrared (MIR) domains. The device characteristics are thoroughly analyzed by the strain distribution,band structure, and absorption characteristics. Numerical and analytical methods show that with optimal structural pa-rameters, the device performance can be further improved and the wavelength application range can be extended to 2~5 μm in the mid-infrared spectra. It is demonstrated that this proposed strategy provides an effective technique for the strained-GeSn devices in future optical designs, which will be competitive for the optoelectronics applications in mid-infrared wavelength.展开更多
International Conference on Nanotechnology, Optoelectronics and Photonics Technologies (NOPT) is an annual International Conference sponsored by Photonics and Microelectronics Society and Components, Packaging & Ma...International Conference on Nanotechnology, Optoelectronics and Photonics Technologies (NOPT) is an annual International Conference sponsored by Photonics and Microelectronics Society and Components, Packaging & Manufacturing Society of IACSIT (International Association of Computer Science and Information Technology),展开更多
Two-dimensional(2D) layered perovskites have emerged as potential alternates to traditional three-dimensional(3D)analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been ...Two-dimensional(2D) layered perovskites have emerged as potential alternates to traditional three-dimensional(3D)analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been spent on manipulating the interlayer organic spacing cation to improve the photovoltaic properties of Dion–Jacobson(DJ) perovskites. In this work, a serious of cycloalkane(CA) molecules were selected as the organic spacing cation in 2D DJ perovskites, which can widely manipulate the optoelectronic properties of the DJ perovskites. The underlying relationship between the CA interlayer molecules and the crystal structures, thermodynamic stabilities, and electronic properties of 58 DJ perovskites has been investigated by using automatic high-throughput workflow cooperated with density-functional(DFT) calculations.We found that these CA-based DJ perovskites are all thermodynamic stable. The sizes of the cycloalkane molecules can influence the degree of inorganic framework distortion and further tune the bandgaps with a wide range of 0.9–2.1 eV.These findings indicate the cycloalkane molecules are suitable as spacing cation in 2D DJ perovskites and provide a useful guidance in designing novel 2D DJ perovskites for optoelectronic applications.展开更多
Gas sensor is an indispensable part of modern society withwide applications in environmental monitoring,healthcare,food industry,public safety,etc.With the development of sensor technology,wireless communication,smart...Gas sensor is an indispensable part of modern society withwide applications in environmental monitoring,healthcare,food industry,public safety,etc.With the development of sensor technology,wireless communication,smart monitoring terminal,cloud storage/computing technology,and artificial intelligence,smart gas sensors represent the future of gassensing due to their merits of real-time multifunctional monitoring,earlywarning function,and intelligent and automated feature.Various electronicand optoelectronic gas sensors have been developed for high-performancesmart gas analysis.With the development of smart terminals and the maturityof integrated technology,flexible and wearable gas sensors play an increasingrole in gas analysis.This review highlights recent advances of smart gassensors in diverse applications.The structural components and fundamentalprinciples of electronic and optoelectronic gas sensors are described,andflexible and wearable gas sensor devices are highlighted.Moreover,sensorarray with artificial intelligence algorithms and smart gas sensors in“Internet of Things”paradigm are introduced.Finally,the challengesand perspectives of smart gas sensors are discussed regarding the future need of gas sensors for smart city and healthy living.展开更多
The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal percept...The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are scarce.Here,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals heterojunctions.Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power consumption.Furthermore,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal perception.This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.展开更多
Neuromorphic hardware equipped with associative learn-ing capabilities presents fascinating applications in the next generation of artificial intelligence.However,research into synaptic devices exhibiting complex asso...Neuromorphic hardware equipped with associative learn-ing capabilities presents fascinating applications in the next generation of artificial intelligence.However,research into synaptic devices exhibiting complex associative learning behaviors is still nascent.Here,an optoelec-tronic memristor based on Ag/TiO_(2) Nanowires:ZnO Quantum dots/FTO was proposed and constructed to emulate the biological associative learning behaviors.Effective implementation of synaptic behaviors,including long and short-term plasticity,and learning-forgetting-relearning behaviors,were achieved in the device through the application of light and electrical stimuli.Leveraging the optoelectronic co-modulated characteristics,a simulation of neuromorphic computing was conducted,resulting in a handwriting digit recognition accuracy of 88.9%.Furthermore,a 3×7 memristor array was constructed,confirming its application in artificial visual memory.Most importantly,complex biological associative learning behaviors were emulated by mapping the light and electrical stimuli into conditioned and unconditioned stimuli,respectively.After training through associative pairs,reflexes could be triggered solely using light stimuli.Comprehen-sively,under specific optoelectronic signal applications,the four features of classical conditioning,namely acquisition,extinction,recovery,and generalization,were elegantly emulated.This work provides an optoelectronic memristor with associative behavior capabilities,offering a pathway for advancing brain-machine interfaces,autonomous robots,and machine self-learning in the future.展开更多
GaN-based devices have developed significantly in recent years due to their promising applications and research potential.A major goal is to monolithically integrate various GaN-based components onto a single chip to ...GaN-based devices have developed significantly in recent years due to their promising applications and research potential.A major goal is to monolithically integrate various GaN-based components onto a single chip to create future optoelectronic systems with low power consumption.This miniaturized integration not only enhances multifunctional performance but also reduces material,processing,and packaging costs.In this study,we present an optoelectronic on-chip system fabricated using a top-down approach on a III-nitride-on-silicon wafer.The system includes a near-ultraviolet light source,a monitor,a 180°bent waveguide,an electro-absorption modulator,and a receiver,all integrated without the need for regrowth or post-growth doping.35 Mbit/s optical data communication is demonstrated through light propagation within the system,confirming its potential for compact GaN-based optoelectronic solutions.展开更多
Research on two-dimensional(2D) materials has been explosively increasing in last seventeen years in varying subjects including condensed matter physics, electronic engineering, materials science, and chemistry since ...Research on two-dimensional(2D) materials has been explosively increasing in last seventeen years in varying subjects including condensed matter physics, electronic engineering, materials science, and chemistry since the mechanical exfoliation of graphene in 2004. Starting from graphene, 2D materials now have become a big family with numerous members and diverse categories. The unique structural features and physicochemical properties of 2D materials make them one class of the most appealing candidates for a wide range of potential applications. In particular, we have seen some major breakthroughs made in the field of 2D materials in last five years not only in developing novel synthetic methods and exploring new structures/properties but also in identifying innovative applications and pushing forward commercialisation. In this review, we provide a critical summary on the recent progress made in the field of 2D materials with a particular focus on last five years. After a brief backgroundintroduction, we first discuss the major synthetic methods for 2D materials, including the mechanical exfoliation, liquid exfoliation, vapor phase deposition, and wet-chemical synthesis as well as phase engineering of 2D materials belonging to the field of phase engineering of nanomaterials(PEN). We then introduce the superconducting/optical/magnetic properties and chirality of 2D materials along with newly emerging magic angle 2D superlattices. Following that, the promising applications of 2D materials in electronics, optoelectronics, catalysis, energy storage, solar cells, biomedicine, sensors, environments, etc. are described sequentially. Thereafter, we present the theoretic calculations and simulations of 2D materials. Finally, after concluding the current progress, we provide some personal discussions on the existing challenges and future outlooks in this rapidly developing field.展开更多
Large-area and high-quality two-dimensional crystals are the basis for the development of the next-generation electronic and optical devices.The synthesis of two-dimensional materials in wafer scales is the first crit...Large-area and high-quality two-dimensional crystals are the basis for the development of the next-generation electronic and optical devices.The synthesis of two-dimensional materials in wafer scales is the first critical step for future technology uptake by the industries;however,currently presented as a significant challenge.Substantial efforts have been devoted to producing atomically thin two-dimensional materials with large lateral dimensions,controllable and uniform thicknesses,large crystal domains and minimum defects.In this review,recent advances in synthetic routes to obtain high-quality two-dimensional crystals with lateral sizes exceeding a hundred micrometres are outlined.Applications of the achieved large-area two-dimensional crystals in electronics and optoelectronics are summarised,and advantages and disadvantages of each approach considering ease of the synthesis,defects,grain sizes and uniformity are discussed.展开更多
A new preparing technology, very high frequency plasma assisted reactive thermal chemical vapour deposition (VHFPA-RTCVD), is introduced to prepare SiGe:H thin films on substrate kept at a lower temperature. In the...A new preparing technology, very high frequency plasma assisted reactive thermal chemical vapour deposition (VHFPA-RTCVD), is introduced to prepare SiGe:H thin films on substrate kept at a lower temperature. In the previous work, reactive thermal chemical vapour deposition (I^TCVD) technology was successfully used to prepare SiGe:H thin films, but the temperature of the substrate needed to exceed 400℃. In this work, very high frequency plasma method is used to assist RTCVD technology in reducing the temperature of substrate by largely enhancing the temperature of reacting gases on the surface of the substrate. The growth rate, structural properties, surface morphology, photo- conductivity and dark-conductivity of SiGe:H thin films prepared by this new technology are investigated for films with different germanium concentrations, and the experimental results are discussed.展开更多
In recent years,significant progress has been achieved in the design and fabrication of stretchable optoelectronic devices.In general,stretchability has been achieved through geometrical modifications of device compon...In recent years,significant progress has been achieved in the design and fabrication of stretchable optoelectronic devices.In general,stretchability has been achieved through geometrical modifications of device components,such as with serpentine interconnects or buckled substrates.However,the local stiffness of individual pixels and the limited pixel density of the array have impeded further advancements in stretchable optoelectronics.Therefore,intrinsically stretch-able optoelectronics have been proposed as an alternative approach.Herein,we review the recent advances in soft elec-tronic materials for application in intrinsically stretchable optoelectronic devices.First,we introduce various intrinsically stretchable electronic materials,comprised of electronic fillers,elastomers,and surfactants,and exemplify different in-trinsically stretchable conducting and semiconducting composites.We also describe the processing methods used to fabricate the electrodes,interconnections,charge transport layers,and optically active layers used in intrinsically stretch-able optoelectronic devices.Subsequently,we review representative examples of intrinsically stretchable optoelectronic devices,including light-emitting capacitors,light-emitting diodes,photodetectors,and photovoltaics.Finally,we briefly discuss intrinsically stretchable integrated optoelectronic systems.展开更多
The paper presents the possibilities of,and methods for,acquiring,analysing and processing optical signals in order to recognise,identify and counteract threats on the contemporary battleground.The main ways electroni...The paper presents the possibilities of,and methods for,acquiring,analysing and processing optical signals in order to recognise,identify and counteract threats on the contemporary battleground.The main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated,including the acquisition of optical emitter signatures,as well as ultraviolet(UV)and thermal(IR)signatures.The physical parameters and values describing the emission of laser radiation are discussed,including their importance in terms of creating optical signatures.Moreover,it has been shown that in the transformation of optical signals into signatures,only their spectral and temporal parameters can be applied.This was confirmed in experimental part of the paper,which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser rangefinders.It has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in“solar-blind”band,various events can be identified quickly and faultlessly.The same is true for IR signatures,where the amplitudes of the recorded signal for several wavelengths are compared.This was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground,namely Rocket Propelled Grenade(RPG)launches and explosions after hitting targets,trinitrotoluene(TNT)explosions,firing armour-piercing,fin-stabilised,discarding sabots(APFSDS)or high explosive(HE)projectiles.The final section describes a proposed model database of emitters,created as a result of analysing and transforming the recorded signals into optical signatures.展开更多
In recent years,metal halide perovskites have received significant attention as materials for next-generation optoelectronic devices owing to their excellent optoelectronic properties.The unprecedented rapid evolution...In recent years,metal halide perovskites have received significant attention as materials for next-generation optoelectronic devices owing to their excellent optoelectronic properties.The unprecedented rapid evolution in the device performance has been achieved by gaining an advanced understanding of the composition,crystal growth,and defect engineering of perovskites.As device performances approach their theoretical limits,effective optical management becomes essential for achieving higher efficiency.In this review,we discuss the status and perspectives of nano to micron-scale patterning methods for the optical management of perovskite optoelectronic devices.We initially discuss the importance of effective light harvesting and light outcoupling via optical management.Subsequently,the recent progress in various patterning/texturing techniques applied to perovskite optoelectronic devices is summarized by categorizing them into top-down and bottom-up methods.Finally,we discuss the perspectives of advanced patterning/texturing technologies for the development and commercialization of perovskite optoelectronic devices.展开更多
Oxide double perovskites A2 B’B"O6 are a class of emerging materials in the fields of optoelectronics and catalysis.Due to the chemical flexibilities of perovskite structures,there are multiple elemental combina...Oxide double perovskites A2 B’B"O6 are a class of emerging materials in the fields of optoelectronics and catalysis.Due to the chemical flexibilities of perovskite structures,there are multiple elemental combinations of cations A,B’,and B",which leading to tremendous candidates.In this study,we comprehensively screened stable oxide double perovskite A2 B’B"O6 from a pool of 2,018 perovskite candidates using a high-throughput computational approach.By considering a tolerance factor(t)-octahedral factor(μ) phase diagram,138 candidates with Fm 3 m, P21/c,and R3 c phases were selected and systematically studied via first-principles calculations based on density functional theory.The screening procedure finally predicted the existence of 21 stable perovskites,and 14 among them have never been reported.Verification with existing experimental results demonstrates that the prediction accuracy for perovskite formability is approximately 90%.The predicted oxide double perovskites exhibit quasi-direct bandgaps ranging from 0 to 4.4 eV with a significantly small direct-indirect bandgap difference,balanced electron and hole effective masses,and strong optical absorptions.The newly predicted oxide double perovskites may enlarge the pool of material candidates for applications in optoelectronics and photocatalysis.This study provides a route for computational screening of novel perovskites for functional applications.展开更多
Crystallographic stability is an important factor that affects the stability of perovskites.The stability dictates the commercial applications of lead-based organometal halide perovskites.The tolerance factor(t)and oc...Crystallographic stability is an important factor that affects the stability of perovskites.The stability dictates the commercial applications of lead-based organometal halide perovskites.The tolerance factor(t)and octahedral factor(μ)form the state-of-the-art criteria used to evaluate the perovskite crystallographic stability.We studied the crystallographic stabilities of halide and chalcogenide perovskites by exploring an effective alternative descriptor,the global instability index(GII)that was used as an indicator of the stability of perovskite oxides.We particularly focused on determining crystallographic reliability by calculating GII.We analyzed the bond valence models of the 243 halide and chalcogenide perovskites that occupied the lowest-energy cubic-phase structures determined by conducting the first-principles-based total energy minimization calculations.The decomposition energy(ΔHD)reflects the thermodynamic stability of the system and is considered as the benchmark that helps assess the effectiveness of GII in evaluating the crystallographic stability of the systems under study.The results indicated that the accuracy of predicting thermodynamic stability was significantly higher when GII(73.6%)was analyzed compared to the cases when t(55%)andμ(39.1%)were analyzed to determine the stability.The results obtained from the machine learning-based data mining method further indicate that GII is an important descriptor of the stability of the perovskite family.展开更多
Semiconductor nanowires, with their unique capability to bridge the nanoscopic and macroscopic worlds, have been demonstrated to have potential applications in energy conversion, electronics, optoelectronics, and bios...Semiconductor nanowires, with their unique capability to bridge the nanoscopic and macroscopic worlds, have been demonstrated to have potential applications in energy conversion, electronics, optoelectronics, and biosensing devices. Onedimensional(1D) ZnO nanostructures, with coupled semiconducting and piezoelectric properties, have been extensively investigated and widely used to fabricate nanoscale optoelectronic devices. In this article, we review recent developments in 1D ZnO nanostructure based photodetectors and device performance enhancement by strain engineering piezoelectric polarization and interface modulation. The emphasis is on a fundamental understanding of electrical and optical phenomena, interfacial and contact behaviors, and device characteristics. Finally, the prospects of 1D ZnO nanostructure devices and new challenges are proposed.展开更多
Two-dimensional(2D)materials are regarded as promising candidates in many applications,including electronics and optoelectronics,because of their superior properties,including atomic-level thickness,tunable bandgaps,l...Two-dimensional(2D)materials are regarded as promising candidates in many applications,including electronics and optoelectronics,because of their superior properties,including atomic-level thickness,tunable bandgaps,large specific surface area,and high carrier mobility.In order to bring 2D materials from the laboratory to industrialized applications,materials preparation is the first prerequisite.Compared to the n-type analogs,the family of p-type 2D semiconductors is relatively small,which limits the broad integration of 2D semiconductors in practical applications such as complementary logic circuits.So far,many efforts have been made in the preparation of p-type 2D semiconductors.In this review,we overview recent progresses achieved in the preparation of p-type 2D semiconductors and highlight some promising methods to realize their controllable preparation by following both the top-down and bottom-up strategies.Then,we summarize some significant application of p-type 2D semiconductors in electronic and optoelectronic devices and their superiorities.In end,we conclude the challenges existed in this field and propose the potential opportunities in aspects from the discovery of novel p-type 2D semiconductors,their controlled mass preparation,compatible engineering with silicon production line,high-κdielectric materials,to integration and applications of p-type 2D semiconductors and their heterostructures in electronic and optoelectronic devices.Overall,we believe that this review will guide the design of preparation systems to fulfill the controllable growth of p-type 2D semiconductors with high quality and thus lay the foundations for their potential application in electronics and optoelectronics.展开更多
We report efficient zero-bias high-speed top-illuminated p-i-n photodiodes (PDs) with high responsivity fabricated with germanium (Ge) films grown directly on silicon-on-insulator (SOI) substrates. For a 15 p-m-...We report efficient zero-bias high-speed top-illuminated p-i-n photodiodes (PDs) with high responsivity fabricated with germanium (Ge) films grown directly on silicon-on-insulator (SOI) substrates. For a 15 p-m-diameter device at room temperature, the dark current density was 44.1 mA/cm2 at -1 V. The responsivity at 1.55 μm was 0.30 A/W at 0 V. The saturation of the optical responsivity at 0 V bias revealed that this photodetector allows a complete photo-generated carrier collection without bias. Although the 3-dB bandwidth of the 15-p.m-diameter detector was 18.8 GHz at the reverse bias of 0 V, the detector responsivity was improved by one order of magnitude compared with that reported in the literature. Moreover, the dark current of the detector was significantly reduced.展开更多
Aim To solve the time delay problem in the optoelectronic tracking system, improving the tracking accuracy. Methods The discount least square algorithm was applied to forecast the tracking error caused by the 40?ms ...Aim To solve the time delay problem in the optoelectronic tracking system, improving the tracking accuracy. Methods The discount least square algorithm was applied to forecast the tracking error caused by the 40?ms delay, and the predicting algorithm was improved by the adaptive discount method.Results The tracking errors of the two methods were compared, and an optimal controller with the improved adaptive discount predicting algorithm was adopted for simulation. Conclusion The predicting algorithms, especially the adaptive discount predicting algorithm, can decrease the tracking error greatly, and the desired tracking prediction can be achieved both in the transient state and in the steady state.展开更多
基金supported by the National Natural Science Foundation of China(51572025,51627801,61435010 and 51702219)the State Key Research Development Program of China(2019YFB2203503)+3 种基金Guangdong Basic and Applied Basic Research Foundation(2019A1515110209)the Science and Technology Innovation Commission of Shenzhen(JCYJ20170818093453105,JCYJ20180305125345378)National Foundation of China(41422050303)Beijing Municipal Science&Technology Commission and the Fundamental Research Funds for Central Universities.
文摘The development of two-dimensional(2D)semiconductors has attracted widespread attentions in the scientific community and industry due to their ultra-thin thickness,unique structure,excellent optoelectronic properties and novel physics.The excellent flexibility and outstanding mechanical strength of 2D semiconductors provide opportunities for fabricated strain-sensitive devices and utilized strain tuning their electronic and optic–electric performance.The strain-engineered one-dimensional materials have been well investigated,while there is a long way to go for 2D semiconductors.In this review,starting with the fundamental theories of piezoelectric and piezoresistive effect resulted by strain,following we reviewed the recent simulation works of strain engineering in novel 2D semiconductors,such as Janus 2D and 2D-Xene structures.Moreover,recent advances in experimental observation of strain tuning PL spectra and transport behavior of 2D semiconductors are summarized.Furthermore,the applications of strain-engineered 2D semiconductors in sensors,photodetectors and nanogenerators are also highlighted.At last,we in-depth discussed future research directions of strain-engineered 2D semiconductor and related electronics and optoelectronics device applications.
基金The authors thank National Natural Science Foundation of China (Grant No. 61534004, 61604112 and 61622405).
文摘We summarize our work of the optoelectronic devices based on Germanium-tin (GeSn) alloys assisted with the Si3N4liner stressor in mid-infrared (MIR) domains. The device characteristics are thoroughly analyzed by the strain distribution,band structure, and absorption characteristics. Numerical and analytical methods show that with optimal structural pa-rameters, the device performance can be further improved and the wavelength application range can be extended to 2~5 μm in the mid-infrared spectra. It is demonstrated that this proposed strategy provides an effective technique for the strained-GeSn devices in future optical designs, which will be competitive for the optoelectronics applications in mid-infrared wavelength.
文摘International Conference on Nanotechnology, Optoelectronics and Photonics Technologies (NOPT) is an annual International Conference sponsored by Photonics and Microelectronics Society and Components, Packaging & Manufacturing Society of IACSIT (International Association of Computer Science and Information Technology),
基金supported by the National Natural Science Foundation of China (Grant No. 62004080)the Postdoctoral Innovative Talents Supporting Program (Grant No. BX20190143)the China Postdoctoral Science Foundation (Grant No. 2020M670834)。
文摘Two-dimensional(2D) layered perovskites have emerged as potential alternates to traditional three-dimensional(3D)analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been spent on manipulating the interlayer organic spacing cation to improve the photovoltaic properties of Dion–Jacobson(DJ) perovskites. In this work, a serious of cycloalkane(CA) molecules were selected as the organic spacing cation in 2D DJ perovskites, which can widely manipulate the optoelectronic properties of the DJ perovskites. The underlying relationship between the CA interlayer molecules and the crystal structures, thermodynamic stabilities, and electronic properties of 58 DJ perovskites has been investigated by using automatic high-throughput workflow cooperated with density-functional(DFT) calculations.We found that these CA-based DJ perovskites are all thermodynamic stable. The sizes of the cycloalkane molecules can influence the degree of inorganic framework distortion and further tune the bandgaps with a wide range of 0.9–2.1 eV.These findings indicate the cycloalkane molecules are suitable as spacing cation in 2D DJ perovskites and provide a useful guidance in designing novel 2D DJ perovskites for optoelectronic applications.
基金supported by the National Natural Science Foundation of China(No.22376159)the Fundamental Research Funds for the Central Universities.
文摘Gas sensor is an indispensable part of modern society withwide applications in environmental monitoring,healthcare,food industry,public safety,etc.With the development of sensor technology,wireless communication,smart monitoring terminal,cloud storage/computing technology,and artificial intelligence,smart gas sensors represent the future of gassensing due to their merits of real-time multifunctional monitoring,earlywarning function,and intelligent and automated feature.Various electronicand optoelectronic gas sensors have been developed for high-performancesmart gas analysis.With the development of smart terminals and the maturityof integrated technology,flexible and wearable gas sensors play an increasingrole in gas analysis.This review highlights recent advances of smart gassensors in diverse applications.The structural components and fundamentalprinciples of electronic and optoelectronic gas sensors are described,andflexible and wearable gas sensor devices are highlighted.Moreover,sensorarray with artificial intelligence algorithms and smart gas sensors in“Internet of Things”paradigm are introduced.Finally,the challengesand perspectives of smart gas sensors are discussed regarding the future need of gas sensors for smart city and healthy living.
基金supported by National Natural Science Foundation of China(No.51902250).
文摘The crossmodal interaction of different senses,which is an important basis for learning and memory in the human brain,is highly desired to be mimicked at the device level for developing neuromorphic crossmodal perception,but related researches are scarce.Here,we demonstrate an optoelectronic synapse for vision-olfactory crossmodal perception based on MXene/violet phosphorus(VP)van der Waals heterojunctions.Benefiting from the efficient separation and transport of photogenerated carriers facilitated by conductive MXene,the photoelectric responsivity of VP is dramatically enhanced by 7 orders of magnitude,reaching up to 7.7 A W^(−1).Excited by ultraviolet light,multiple synaptic functions,including excitatory postsynaptic currents,pairedpulse facilitation,short/long-term plasticity and“learning-experience”behavior,were demonstrated with a low power consumption.Furthermore,the proposed optoelectronic synapse exhibits distinct synaptic behaviors in different gas environments,enabling it to simulate the interaction of visual and olfactory information for crossmodal perception.This work demonstrates the great potential of VP in optoelectronics and provides a promising platform for applications such as virtual reality and neurorobotics.
基金This work was supported by the Jinan City-University Integrated Development Strategy Project under Grant(JNSX2023017)National Research Foundation of Korea(NRF)grant funded by the Korea government(MIST)(RS-2023-00302751)+1 种基金by the National Research Foundation of Korea(NRF)funded by the Ministry of Education under Grants 2018R1A6A1A03025242 and 2018R1D1A1A09083353by Qilu Young Scholar Program of Shandong University.
文摘Neuromorphic hardware equipped with associative learn-ing capabilities presents fascinating applications in the next generation of artificial intelligence.However,research into synaptic devices exhibiting complex associative learning behaviors is still nascent.Here,an optoelec-tronic memristor based on Ag/TiO_(2) Nanowires:ZnO Quantum dots/FTO was proposed and constructed to emulate the biological associative learning behaviors.Effective implementation of synaptic behaviors,including long and short-term plasticity,and learning-forgetting-relearning behaviors,were achieved in the device through the application of light and electrical stimuli.Leveraging the optoelectronic co-modulated characteristics,a simulation of neuromorphic computing was conducted,resulting in a handwriting digit recognition accuracy of 88.9%.Furthermore,a 3×7 memristor array was constructed,confirming its application in artificial visual memory.Most importantly,complex biological associative learning behaviors were emulated by mapping the light and electrical stimuli into conditioned and unconditioned stimuli,respectively.After training through associative pairs,reflexes could be triggered solely using light stimuli.Comprehen-sively,under specific optoelectronic signal applications,the four features of classical conditioning,namely acquisition,extinction,recovery,and generalization,were elegantly emulated.This work provides an optoelectronic memristor with associative behavior capabilities,offering a pathway for advancing brain-machine interfaces,autonomous robots,and machine self-learning in the future.
基金This work was supported in part by the National Natural Science Founda⁃tion of China under Grant No.U21A20495National Key Research and De⁃velopment Program of China under Grant No.2022YFE0112000High⁃er Education Discipline Innovation Project under Grant No.D17018.
文摘GaN-based devices have developed significantly in recent years due to their promising applications and research potential.A major goal is to monolithically integrate various GaN-based components onto a single chip to create future optoelectronic systems with low power consumption.This miniaturized integration not only enhances multifunctional performance but also reduces material,processing,and packaging costs.In this study,we present an optoelectronic on-chip system fabricated using a top-down approach on a III-nitride-on-silicon wafer.The system includes a near-ultraviolet light source,a monitor,a 180°bent waveguide,an electro-absorption modulator,and a receiver,all integrated without the need for regrowth or post-growth doping.35 Mbit/s optical data communication is demonstrated through light propagation within the system,confirming its potential for compact GaN-based optoelectronic solutions.
文摘Research on two-dimensional(2D) materials has been explosively increasing in last seventeen years in varying subjects including condensed matter physics, electronic engineering, materials science, and chemistry since the mechanical exfoliation of graphene in 2004. Starting from graphene, 2D materials now have become a big family with numerous members and diverse categories. The unique structural features and physicochemical properties of 2D materials make them one class of the most appealing candidates for a wide range of potential applications. In particular, we have seen some major breakthroughs made in the field of 2D materials in last five years not only in developing novel synthetic methods and exploring new structures/properties but also in identifying innovative applications and pushing forward commercialisation. In this review, we provide a critical summary on the recent progress made in the field of 2D materials with a particular focus on last five years. After a brief backgroundintroduction, we first discuss the major synthetic methods for 2D materials, including the mechanical exfoliation, liquid exfoliation, vapor phase deposition, and wet-chemical synthesis as well as phase engineering of 2D materials belonging to the field of phase engineering of nanomaterials(PEN). We then introduce the superconducting/optical/magnetic properties and chirality of 2D materials along with newly emerging magic angle 2D superlattices. Following that, the promising applications of 2D materials in electronics, optoelectronics, catalysis, energy storage, solar cells, biomedicine, sensors, environments, etc. are described sequentially. Thereafter, we present the theoretic calculations and simulations of 2D materials. Finally, after concluding the current progress, we provide some personal discussions on the existing challenges and future outlooks in this rapidly developing field.
基金the financial support from“National Natural Science Foundation of China”(No.51850410506)。
文摘Large-area and high-quality two-dimensional crystals are the basis for the development of the next-generation electronic and optical devices.The synthesis of two-dimensional materials in wafer scales is the first critical step for future technology uptake by the industries;however,currently presented as a significant challenge.Substantial efforts have been devoted to producing atomically thin two-dimensional materials with large lateral dimensions,controllable and uniform thicknesses,large crystal domains and minimum defects.In this review,recent advances in synthetic routes to obtain high-quality two-dimensional crystals with lateral sizes exceeding a hundred micrometres are outlined.Applications of the achieved large-area two-dimensional crystals in electronics and optoelectronics are summarised,and advantages and disadvantages of each approach considering ease of the synthesis,defects,grain sizes and uniformity are discussed.
基金supported by the State Key Development Program for Basic Research of China (Grant Nos 2006CB202602 and 2006CB202603)the Tianjin Research Foundation for Basic Research,China (Grant No 08JCZDJC 22200)International Cooperative Project of the Ministry of Science and Technology,China (Grant No 2006DFA62390)
文摘A new preparing technology, very high frequency plasma assisted reactive thermal chemical vapour deposition (VHFPA-RTCVD), is introduced to prepare SiGe:H thin films on substrate kept at a lower temperature. In the previous work, reactive thermal chemical vapour deposition (I^TCVD) technology was successfully used to prepare SiGe:H thin films, but the temperature of the substrate needed to exceed 400℃. In this work, very high frequency plasma method is used to assist RTCVD technology in reducing the temperature of substrate by largely enhancing the temperature of reacting gases on the surface of the substrate. The growth rate, structural properties, surface morphology, photo- conductivity and dark-conductivity of SiGe:H thin films prepared by this new technology are investigated for films with different germanium concentrations, and the experimental results are discussed.
基金supported by Institute for Basic Science(IBS-R006-A1)supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education(2021R1I1A1A01060389).
文摘In recent years,significant progress has been achieved in the design and fabrication of stretchable optoelectronic devices.In general,stretchability has been achieved through geometrical modifications of device components,such as with serpentine interconnects or buckled substrates.However,the local stiffness of individual pixels and the limited pixel density of the array have impeded further advancements in stretchable optoelectronics.Therefore,intrinsically stretch-able optoelectronics have been proposed as an alternative approach.Herein,we review the recent advances in soft elec-tronic materials for application in intrinsically stretchable optoelectronic devices.First,we introduce various intrinsically stretchable electronic materials,comprised of electronic fillers,elastomers,and surfactants,and exemplify different in-trinsically stretchable conducting and semiconducting composites.We also describe the processing methods used to fabricate the electrodes,interconnections,charge transport layers,and optically active layers used in intrinsically stretch-able optoelectronic devices.Subsequently,we review representative examples of intrinsically stretchable optoelectronic devices,including light-emitting capacitors,light-emitting diodes,photodetectors,and photovoltaics.Finally,we briefly discuss intrinsically stretchable integrated optoelectronic systems.
基金the National Center for Research and Development in Poland for grant No.DOB-1-6/1/PS/2014:“Laser Systems for Directed Energy Weapon,Laser Systems for Non-LethalWeapon”,which provided a proportion of the funds needed to conduct this research.
文摘The paper presents the possibilities of,and methods for,acquiring,analysing and processing optical signals in order to recognise,identify and counteract threats on the contemporary battleground.The main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated,including the acquisition of optical emitter signatures,as well as ultraviolet(UV)and thermal(IR)signatures.The physical parameters and values describing the emission of laser radiation are discussed,including their importance in terms of creating optical signatures.Moreover,it has been shown that in the transformation of optical signals into signatures,only their spectral and temporal parameters can be applied.This was confirmed in experimental part of the paper,which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser rangefinders.It has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in“solar-blind”band,various events can be identified quickly and faultlessly.The same is true for IR signatures,where the amplitudes of the recorded signal for several wavelengths are compared.This was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground,namely Rocket Propelled Grenade(RPG)launches and explosions after hitting targets,trinitrotoluene(TNT)explosions,firing armour-piercing,fin-stabilised,discarding sabots(APFSDS)or high explosive(HE)projectiles.The final section describes a proposed model database of emitters,created as a result of analysing and transforming the recorded signals into optical signatures.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2020R1I1A3054824)supported by the Basic Research Program through the NRF funded by the MSIT(Ministry of Science and ICT,2021R1A4A1032762)+2 种基金financial support by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)the Ministry of Trade,Industry&Energy(MOTIE)of the Republic of Korea(no.20213030010400)the financial support by the NRF grant funded by the MSIT under the contract numbers 2022R1C1C1011975。
文摘In recent years,metal halide perovskites have received significant attention as materials for next-generation optoelectronic devices owing to their excellent optoelectronic properties.The unprecedented rapid evolution in the device performance has been achieved by gaining an advanced understanding of the composition,crystal growth,and defect engineering of perovskites.As device performances approach their theoretical limits,effective optical management becomes essential for achieving higher efficiency.In this review,we discuss the status and perspectives of nano to micron-scale patterning methods for the optical management of perovskite optoelectronic devices.We initially discuss the importance of effective light harvesting and light outcoupling via optical management.Subsequently,the recent progress in various patterning/texturing techniques applied to perovskite optoelectronic devices is summarized by categorizing them into top-down and bottom-up methods.Finally,we discuss the perspectives of advanced patterning/texturing technologies for the development and commercialization of perovskite optoelectronic devices.
基金the funding support from the National Key Research and Development Program of China(Grant 2016YFB0700700)National Natural Science Foundation of China(Grants 11674237,11974257)+1 种基金Priority Academic program Development of Jiangsu Higher Education Institutions(PAPD)Suzhou Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies,China。
文摘Oxide double perovskites A2 B’B"O6 are a class of emerging materials in the fields of optoelectronics and catalysis.Due to the chemical flexibilities of perovskite structures,there are multiple elemental combinations of cations A,B’,and B",which leading to tremendous candidates.In this study,we comprehensively screened stable oxide double perovskite A2 B’B"O6 from a pool of 2,018 perovskite candidates using a high-throughput computational approach.By considering a tolerance factor(t)-octahedral factor(μ) phase diagram,138 candidates with Fm 3 m, P21/c,and R3 c phases were selected and systematically studied via first-principles calculations based on density functional theory.The screening procedure finally predicted the existence of 21 stable perovskites,and 14 among them have never been reported.Verification with existing experimental results demonstrates that the prediction accuracy for perovskite formability is approximately 90%.The predicted oxide double perovskites exhibit quasi-direct bandgaps ranging from 0 to 4.4 eV with a significantly small direct-indirect bandgap difference,balanced electron and hole effective masses,and strong optical absorptions.The newly predicted oxide double perovskites may enlarge the pool of material candidates for applications in optoelectronics and photocatalysis.This study provides a route for computational screening of novel perovskites for functional applications.
基金supported by the National Natural Science Foundation of China(62004080 and 92061113)the Postdoctoral Innovative Talents Supporting Program(BX20190143)the China Postdoctoral Science Foundation(2020M670834)。
文摘Crystallographic stability is an important factor that affects the stability of perovskites.The stability dictates the commercial applications of lead-based organometal halide perovskites.The tolerance factor(t)and octahedral factor(μ)form the state-of-the-art criteria used to evaluate the perovskite crystallographic stability.We studied the crystallographic stabilities of halide and chalcogenide perovskites by exploring an effective alternative descriptor,the global instability index(GII)that was used as an indicator of the stability of perovskite oxides.We particularly focused on determining crystallographic reliability by calculating GII.We analyzed the bond valence models of the 243 halide and chalcogenide perovskites that occupied the lowest-energy cubic-phase structures determined by conducting the first-principles-based total energy minimization calculations.The decomposition energy(ΔHD)reflects the thermodynamic stability of the system and is considered as the benchmark that helps assess the effectiveness of GII in evaluating the crystallographic stability of the systems under study.The results indicated that the accuracy of predicting thermodynamic stability was significantly higher when GII(73.6%)was analyzed compared to the cases when t(55%)andμ(39.1%)were analyzed to determine the stability.The results obtained from the machine learning-based data mining method further indicate that GII is an important descriptor of the stability of the perovskite family.
基金Project supported by the National Major Research Program of China(Grant No.2013CB932602)the National Key Research and Development Program of China(Grant No.2016YFA0202701)+6 种基金the Program of Introducing Talents of Discipline to Universities,China(Grant No.B14003)the National Natural Science Foundation of China(Grant Nos.51527802,51232001,51602020,51672026,and 51372020)China Postdoctoral Science Foundation(Grant Nos.2015M580981 and 2016T90033)Beijing Municipal Science&Technology Commission,Chinathe State Key Laboratory for Advanced Metals and Materials,China(Grant No.2016Z-06)the Fundamental Research Funds for the Central Universities,ChinaJST in Japan,Research and Education Consortium for Innovation of Advanced Integrated Science
文摘Semiconductor nanowires, with their unique capability to bridge the nanoscopic and macroscopic worlds, have been demonstrated to have potential applications in energy conversion, electronics, optoelectronics, and biosensing devices. Onedimensional(1D) ZnO nanostructures, with coupled semiconducting and piezoelectric properties, have been extensively investigated and widely used to fabricate nanoscale optoelectronic devices. In this article, we review recent developments in 1D ZnO nanostructure based photodetectors and device performance enhancement by strain engineering piezoelectric polarization and interface modulation. The emphasis is on a fundamental understanding of electrical and optical phenomena, interfacial and contact behaviors, and device characteristics. Finally, the prospects of 1D ZnO nanostructure devices and new challenges are proposed.
基金support from the National Natural Science Foundation of China (Nos. 52202044 and 52302190)Suzhou Science and Technology Program for Industrial Prospect and Key technology (No. SYC2022018)
文摘Two-dimensional(2D)materials are regarded as promising candidates in many applications,including electronics and optoelectronics,because of their superior properties,including atomic-level thickness,tunable bandgaps,large specific surface area,and high carrier mobility.In order to bring 2D materials from the laboratory to industrialized applications,materials preparation is the first prerequisite.Compared to the n-type analogs,the family of p-type 2D semiconductors is relatively small,which limits the broad integration of 2D semiconductors in practical applications such as complementary logic circuits.So far,many efforts have been made in the preparation of p-type 2D semiconductors.In this review,we overview recent progresses achieved in the preparation of p-type 2D semiconductors and highlight some promising methods to realize their controllable preparation by following both the top-down and bottom-up strategies.Then,we summarize some significant application of p-type 2D semiconductors in electronic and optoelectronic devices and their superiorities.In end,we conclude the challenges existed in this field and propose the potential opportunities in aspects from the discovery of novel p-type 2D semiconductors,their controlled mass preparation,compatible engineering with silicon production line,high-κdielectric materials,to integration and applications of p-type 2D semiconductors and their heterostructures in electronic and optoelectronic devices.Overall,we believe that this review will guide the design of preparation systems to fulfill the controllable growth of p-type 2D semiconductors with high quality and thus lay the foundations for their potential application in electronics and optoelectronics.
文摘We report efficient zero-bias high-speed top-illuminated p-i-n photodiodes (PDs) with high responsivity fabricated with germanium (Ge) films grown directly on silicon-on-insulator (SOI) substrates. For a 15 p-m-diameter device at room temperature, the dark current density was 44.1 mA/cm2 at -1 V. The responsivity at 1.55 μm was 0.30 A/W at 0 V. The saturation of the optical responsivity at 0 V bias revealed that this photodetector allows a complete photo-generated carrier collection without bias. Although the 3-dB bandwidth of the 15-p.m-diameter detector was 18.8 GHz at the reverse bias of 0 V, the detector responsivity was improved by one order of magnitude compared with that reported in the literature. Moreover, the dark current of the detector was significantly reduced.
文摘Aim To solve the time delay problem in the optoelectronic tracking system, improving the tracking accuracy. Methods The discount least square algorithm was applied to forecast the tracking error caused by the 40?ms delay, and the predicting algorithm was improved by the adaptive discount method.Results The tracking errors of the two methods were compared, and an optimal controller with the improved adaptive discount predicting algorithm was adopted for simulation. Conclusion The predicting algorithms, especially the adaptive discount predicting algorithm, can decrease the tracking error greatly, and the desired tracking prediction can be achieved both in the transient state and in the steady state.