Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of e...Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of editable superconducting diodes could unlock transformative applications,including dynamically reconfigurable quantum circuits that adapt to operational requirements.Here,we report the first observation of the superconducting diode effect(SDE)in LaAlO_(3)/KTaO_(3) heterostructures—a two-dimensional oxide interface superconductor with exceptional tunability.We observe a strong SDE in Hall-bar(or strip-shaped)devices under perpendicular magnetic fields(<15 Oe),with efficiencies above 40%and rectification signals exceeding 10 mV.Through conductive atomic force microscope lithography,we demonstrate reversible nanoscale editing of the SDE’s polarity and efficiency by locally modifying the superconducting channel edges.This approach enables multiple nonvolatile configurations within a single device,realizing an editable superconducting diode.Our work establishes LaAlO_(3)/KTaO_(3) as a platform for vortex-based nonreciprocal transport and provides a pathway toward designer quantum circuits with on-demand functionalities.展开更多
Tunneling diodes hold significant promise for future rectification in the terahertz(THz)and visible light spectra,thanks to their femtosecond-scale transit-time tunneling capabilities.In this work,TiN/ZnO/Pt fin tunne...Tunneling diodes hold significant promise for future rectification in the terahertz(THz)and visible light spectra,thanks to their femtosecond-scale transit-time tunneling capabilities.In this work,TiN/ZnO/Pt fin tunneling diodes(FTDs)with tunneling distances of 10 and 5 nm are fabricated,which demonstrate remarkable characteristics,including ultrahigh asymmetry(1.6×10^(4)for 10 nm device and 1.6×10^(3) for 5 nm device),high responsivity(25.3 V^(-1) for 10 nm device and 28.3 V^(-1) for 5 nm device)at zero bias,surpassing the thermal voltage limit of conventional Schottky diodes,and low turn-on voltage(V_(on))of approximately 100 mV for both devices,making them ideal for power conversion applications.Using technology computer-aided design(TCAD)simulations,the observed asymmetry in electronic transport is attributed to the transition between Fowler-Nordheim tunneling(FNT)and trap-assisted tunneling(TAT)under different biasing conditions,as illustrated by the corresponding energy band profiles.Furthermore,by integrating the FTDs,a rectifier bridge circuit is designed and exhibits full-wave rectification behavior,validated through SPICE simulations for THz-band operations.This advancement offers a highly efficient solution for THz-band energy conversion and effective detection applications.展开更多
AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layer...AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layers(EBLs).To overcome these limitations,we propose an EBL-free DUV LD design incor-porating a 1-nm undoped Al_(0.8)Ga_(0.2)N thin strip layer after the last quantum barrier.Using PICS3D simula-tions,we evaluate the optical and electrical characteristics.Results show a significant increase in effective electron barrier height(from 158.2 meV to 420.7 meV)and a reduction in hole barrier height(from 149.2 meV to 62.8 meV),which enhance hole injection and reduce electron leakage.The optimized structure(LD3)achieves a 14%increase in output power,improved slope efficiency(1.85 W/A),and lower threshold current.This design also reduces the quantum confined Stark effect and forms dual hole accumulation regions,im-proving recombination efficiency.展开更多
Metal halide perovskites have emerged as highly promising candidates for the emissive layer in next-generation light-emitting diodes(LEDs)due to their narrow emission linewidths,high photoluminescence quantum yields,a...Metal halide perovskites have emerged as highly promising candidates for the emissive layer in next-generation light-emitting diodes(LEDs)due to their narrow emission linewidths,high photoluminescence quantum yields,and tunable emission wavelengths.Achieving high-performance perovskite LEDs(Pe LEDs)requires the emissive layer to possess efficient radiative recombination,low defect density,minimal ion mobility,and effective carrier confinement.Perovskite/perovskite heterostructure(PPHS)offers a compelling approach for engineering emissive layers with these desired attributes,owing to their ability to passivate surface defects,tailor bandgaps,and suppress ion migration.Pe LEDs based on PPHS have demonstrated superior performance compared to single-phase devices,particularly in terms of external quantum efficiency and operational stability.This review provides a comprehensive overview of the typical PPHS architectures applied in Pe LEDs,including vertical,lateral,and bulk configurations.We discuss representative fabrication strategies and the associated optoelectronic properties of these heterostructures,highlighting the mechanisms by which they enhance device efficiency and stability.Finally,we explore the remaining challenges and prospects for the application of PPHS in Pe LEDs and other luminescent technologies.展开更多
This study presents aβ-Ga_(2)O_(3)diode featuring a Fin-channel structure and an anode ohmic contact.The device turnoff is facilitated by the depletion effect induced by the work function difference between the sidew...This study presents aβ-Ga_(2)O_(3)diode featuring a Fin-channel structure and an anode ohmic contact.The device turnoff is facilitated by the depletion effect induced by the work function difference between the sidewall metal andβ-Ga_(2)O_(3).As the forward bias increases,electron accumulation occurs on the Fin-channel sidewalls,reducing the on-resistance and improving the forward characteristics.Moreover,the device exhibits the reduced surface field(RESURF)effect,similar to trench schottky barrier diodes(SBDs),which shifts the electric field at the fin corners and enhances the breakdown voltage.For a device with a 100 nm fin width(W_(fin)),we achieved a breakdown voltage(BV)of 1137 V,a specific on-resistance(R_(on,sp))of 1.8 mΩ·cm^(2),and a power figure of merit(PFOM)of 0.72 GW/cm^(2).This work expands the fabrication approach forβ-Ga_(2)O_(3)-based devices,advancing their potential for high-performance applications.展开更多
Owing to the exceptional optoelectronic properties,metal halide perovskites have emerged as leading semiconductor materials for next-generation display technologies,providing perovskite light-emitting diodes(Pe LEDs)g...Owing to the exceptional optoelectronic properties,metal halide perovskites have emerged as leading semiconductor materials for next-generation display technologies,providing perovskite light-emitting diodes(Pe LEDs)great potential for high-quality color displays with a wide color gamut and pure color emission.Although laboratory-scale Pe LEDs have achieved neartheoretical efficiencies,challenges such as achieving uniform large-area films,improving material stability,and enhancing patterning precision remain barriers to commercialization.This review presents a systematic analysis of scalable manufacturing and precision patterning strategies for Pe LEDs,focusing on their applications in large-area lighting and full-color displays.Fabrication methods are categorized into film deposition techniques(spin-coating,blade-coating,and thermal evaporation)and patterning strategies,including top-down(photolithography,laser/e-beam lithography,and nanoimprinting)and bottom-up(patterned crystal growth,inkjet printing,and electrohydrodynamic jet printing)approaches.In this review,we discuss the advantages and limitations of each strategy,highlight current challenges,and outlook possible pathways towards scalable,high-performance Pe LEDs for advanced optoelectronic applications.展开更多
Electrodeposited organic light-emitting diode(OLED)technology requires a spin-coating-free hole-injection layer that simultaneously provides smooth surface morphology,stable energy levels,and compatibility with high-r...Electrodeposited organic light-emitting diode(OLED)technology requires a spin-coating-free hole-injection layer that simultaneously provides smooth surface morphology,stable energy levels,and compatibility with high-resolution pixel architectures.In this study,electropolymerization of 3,4-ethylenedioxythiophene(EDOT)in poly(styrene sulfonate)(PSS-)surfactant-solubilized colloidal media is shown to afford poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)films with robust surface uniformity and stable energy levels suitable for application as hole-injection layers in OLEDs.Systematic investigation reveals that the hole-injection properties of these films are governed primarily by the colloidal chemistry of EDOT/PSS-surfactant-solubilized systems,rather than by conventional electrochemical parameters.This colloidal regulation modulates the film work function over a practically useful range.Incorporation of optimized films into OLEDs leads to enhanced hole injection and improved device performance,with external quantum efficiency increasing from 2.2%to 7.4%and minimal roll-off.Overall,this work demonstrates a feasible example of realizing spin-coating-free hole-injection layers,offering a potential direction for the development of electrodeposited injection layers for OLEDs.展开更多
To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polym...To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics.展开更多
Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LED...Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LEDs[7,8].However,it took much longer time for GaN-based LDs to achieve high power,high wall plug efficiency,and long lifetime.Until 2019,Nichia reported blue LDs with these performances[9],which open wide applications with GaN-based blue LDs.展开更多
Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yiel...Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.展开更多
Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hin...Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hinder system integration due to their specific manufacturing processes.Conversely,metal oxide diodes,with their simple fabrication techniques,offer advantages for system integration.The oxygen vacancy defect of oxide semiconductor will greatly affect the electrical performance of the device,so the performance of the diode can be effectively controlled by adjusting the oxygen vacancy concentration.This study centers on optimizing the performance of diodes by modulating the oxygen vacancy concentration within InGaZnO films through control of oxygen flows during the sputtering process.Experimental results demonstrate that the diode exhibits a forward current density of 43.82 A·cm^(−2),with a rectification ratio of 6.94×10^(4),efficiently rectifying input sine signals with 1 kHz frequency and 5 V magnitude.These results demonstrate its potential in energy conversion and management.By adjusting the oxygen vacancy,a methodology is provided for optimizing the performance of rectifying diodes.展开更多
The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investiga...The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investigates how quantum confinement governs the charge transport,exciton dynamics,and emission efficiency in QD-LEDs,using CsPbI_(3) QDs as a model system.By systematically varying QD sizes,we reveal size-dependent trade-offs in LED performance,such as enhanced efficiency for smaller QDs but increased brightness and stability for larger QDs under high current densities.Our findings offer critical insights into the design of high-performance QD-LEDs,paving the way for scalable and energy-efficient optoelectronic devices.展开更多
There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresse...There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.展开更多
We investigate the possible Josephson diode effect(JDE)in a two-dimensional(2D)nonmagnetic planar s-wave superconductor junction,which is constructed on a spin-collinear d-wave altermagnet(AM)material in the presence ...We investigate the possible Josephson diode effect(JDE)in a two-dimensional(2D)nonmagnetic planar s-wave superconductor junction,which is constructed on a spin-collinear d-wave altermagnet(AM)material in the presence of Rashba spin-orbit interaction.It is demonstrated that the JDE is critically dependent on the crystalline axis of the AM relative to the current direction.The d_(x^(2)-y^(2))magnetization symmetry can support a JDE whereas the dxy symmetry does not facilitate it.The JDE efficiency can reach up to 40%and can be adjusted by an additional asymmetric gate voltage applied to the non-superconducting region of the junction,including control of its polarity.Our findings provide an electrical means to control the JDE within a non-magnetic AM-based superconducting junction.展开更多
Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution g...Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution grids.This study measures the effectiveness of the Puma optimizer(PO)algorithm in parameter estimation of PSC(perovskite solar cells)dynamic models with hysteresis consideration considering the electric field effects on operation.The models used in this study will incorporate hysteresis effects to capture the time-dependent behavior of PSCs accurately.The PO optimizes the proposed modified triple diode model(TDM)with a variable voltage capacitor and resistances(VVCARs)considering the hysteresis behavior.The suggested PO algorithm contrasts with other wellknown optimizers from the literature to demonstrate its superiority.The results emphasize that the PO realizes a lower RMSE(Root mean square errors),which proves its capability and efficacy in parameter extraction for the models.The statistical results emphasize the efficiency and supremacy of the proposed PO compared to the other well-known competing optimizers.The convergence rates show good,fast,and stable convergence rates with lower RMSE via PO compared to the other five competitive optimizers.Moreover,the lowermean realized via the PO optimizer is illustrated by the box plot for all optimizers.展开更多
Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting...Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting the chemical potential of moisture into electric energy through interactions with hygroscopic materials and nanostructured interfaces.Unlike solar or thermal harvesters,MEGs operate continuously by utilizing ubiquitous atmospheric moisture,granting them unique spatial and temporal adaptability.Despite nearly a decade of progress and the exploration of diverse material systems for MEG,the overall output power remains significantly limited due to inherently low charge carrier concentrations and restricted ion diffusion fluxes[2].As a result,standalone MEG devices often deliver low and unstable output,limiting practical applications.To enhance performance and versatility,recent efforts have explored hybridization of MEG with other ambient energy sources such as triboelectric or thermoelectric effects.展开更多
Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancement...Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancements have been made in the performance of cadmium-free QLEDs.However,several challenges persist in the industrialization of ecofriendly QLED displays.For instance,(1)the poor performance,characterized by low photoluminescence quantum yield(PLQY),unstable ligand,and charge imbalance,cannot be effectively addressed with a solitary strategy;(2)the degradation mechanism,involving emission quenching,morphological inhomogeneity,and field-enhanced electron delocalization remains unclear;(3)the lack of techniques for color patterning,such as optical lithography and transfer printing.Herein,we undertake a specific review of all technological breakthroughs that endeavor to tackle the above challenges associated with cadmium-free QLED displays.We begin by reviewing the evolution,architecture,and operational characteristics of eco-friendly QLEDs,highlighting the photoelectric properties of QDs,carrier transport layer stability,and device lifetime.Subsequently,we focus our attention not only on the latest insights into device degradation mechanisms,particularly,but also on the remarkable technological progress in color patterning techniques.To conclude,we provide a synthesis of the promising prospects,current challenges,potential solutions,and emerging research trends for QLED displays.展开更多
Carbon dots(CDs),due to their low cost,high stability,and high luminous efficiency,have emerged as an excellent material for the emissive layer in next-generation electroluminescent light-emitting diodes(ELEDs).Howeve...Carbon dots(CDs),due to their low cost,high stability,and high luminous efficiency,have emerged as an excellent material for the emissive layer in next-generation electroluminescent light-emitting diodes(ELEDs).However,improving the efficiency of fluorescent CDs-based ELEDs remains challenging,primarily because it is difficult to utilize triplet excitons in the electroluminescence process.Therefore,enhancing the exciton utilization efficiency of CDs during electroluminescence is crucial.Based on this,we exploited the characteristic large exciton binding energy commonly found in CDs to develop exciton-emitting CDs.These CDs facilitate the radiative recombination of excitons during electroluminescence,thereby improving the electroluminescent efficiency.By rationally selecting precursors,we developed high quantum efficiency CDs and subsequently constructed CDs-based ELEDs.The blue-light device exhibited an external quantum efficiency of over 4%.This study introduces a novel design concept for CDs,providing a new strategy for developing high-performance blue ELEDs based on CDs.展开更多
GaN diodes for high energy(64.8 MeV)proton detection were fabricated and investigated.A comparison of the performance of GaN diodes with different structures is presented,with a focus on sapphire and on GaN substrates...GaN diodes for high energy(64.8 MeV)proton detection were fabricated and investigated.A comparison of the performance of GaN diodes with different structures is presented,with a focus on sapphire and on GaN substrates,Schottky and pin diodes,and different active layer thicknesses.Pin diodes fabricated on a sapphire substrate are the best choice for a GaN proton detector working at 0 V bias.They are sensitive(minimum detectable proton beam<1 pA/cm^(2)),linear as a function of proton current and fast(<1 s).High proton current sensitivity and high spatial resolution of GaN diodes can be exploited in the future for proton imaging of patients in proton therapy.展开更多
Background Plant tissue culture has emerged as a tool for improving cotton propagation and genetics,but recalcitrance nature of cotton makes it difficult to develop in vitro regeneration.Cotton’s recalcitrance is inf...Background Plant tissue culture has emerged as a tool for improving cotton propagation and genetics,but recalcitrance nature of cotton makes it difficult to develop in vitro regeneration.Cotton’s recalcitrance is influenced by genotype,explant type,and environmental conditions.To overcome these issues,this study uses different machine learning-based predictive models by employing multiple input factors.Cotyledonary node explants of two commercial cotton cultivars(STN-468 and GSN-12)were isolated from 7–8 days old seedlings,preconditioned with 5,10,and 20 mg·L^(-1) kinetin(KIN)for 10 days.Thereafter,explants were postconditioned on full Murashige and Skoog(MS),1/2MS,1/4MS,and full MS+0.05 mg·L^(-1) KIN,cultured in growth room enlightened with red and blue light-emitting diodes(LED)combination.Statistical analysis(analysis of variance,regression analysis)was employed to assess the impact of different treatments on shoot regeneration,with artificial intelligence(AI)models used for confirming the findings.Results GSN-12 exhibited superior shoot regeneration potential compared with STN-468,with an average of 4.99 shoots per explant versus 3.97.Optimal results were achieved with 5 mg·L^(-1) KIN preconditioning,1/4MS postconditioning,and 80%red LED,with maximum of 7.75 shoot count for GSN-12 under these conditions;while STN-468 reached 6.00 shoots under the conditions of 10 mg·L^(-1) KIN preconditioning,MS with 0.05 mg·L^(-1) KIN(postconditioning)and 75.0%red LED.Rooting was successfully achieved with naphthalene acetic acid and activated charcoal.Additionally,three different powerful AI-based models,namely,extreme gradient boost(XGBoost),random forest(RF),and the artificial neural network-based multilayer perceptron(MLP)regression models validated the findings.Conclusion GSN-12 outperformed STN-468 with optimal results from 5 mg·L^(-1) KIN+1/4MS+80%red LED.Application of machine learning-based prediction models to optimize cotton tissue culture protocols for shoot regeneration is helpful to improve cotton regeneration efficiency.展开更多
基金supported by the National Key R&D Program of China (Grant No.2023YFA1406400)the National Natural Science Foundation of China (Grant Nos.12534005 and 12325402)。
文摘Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of editable superconducting diodes could unlock transformative applications,including dynamically reconfigurable quantum circuits that adapt to operational requirements.Here,we report the first observation of the superconducting diode effect(SDE)in LaAlO_(3)/KTaO_(3) heterostructures—a two-dimensional oxide interface superconductor with exceptional tunability.We observe a strong SDE in Hall-bar(or strip-shaped)devices under perpendicular magnetic fields(<15 Oe),with efficiencies above 40%and rectification signals exceeding 10 mV.Through conductive atomic force microscope lithography,we demonstrate reversible nanoscale editing of the SDE’s polarity and efficiency by locally modifying the superconducting channel edges.This approach enables multiple nonvolatile configurations within a single device,realizing an editable superconducting diode.Our work establishes LaAlO_(3)/KTaO_(3) as a platform for vortex-based nonreciprocal transport and provides a pathway toward designer quantum circuits with on-demand functionalities.
基金National Key Research and Development Program of China(2024YFA1410700,2021YFA1200700)National Natural Science Foundation of China(62474065,T2222025,62174053)+3 种基金Natural Science Foundation of Chongqing(CSTB2024NSCQ-JQX0005)Shanghai Science and Technology Innovation Action Plan(24QA2702300,24YF2710400)National Postdoctoral Program(GZB20240225)Fundamental Research Funds for the Central Universities。
文摘Tunneling diodes hold significant promise for future rectification in the terahertz(THz)and visible light spectra,thanks to their femtosecond-scale transit-time tunneling capabilities.In this work,TiN/ZnO/Pt fin tunneling diodes(FTDs)with tunneling distances of 10 and 5 nm are fabricated,which demonstrate remarkable characteristics,including ultrahigh asymmetry(1.6×10^(4)for 10 nm device and 1.6×10^(3) for 5 nm device),high responsivity(25.3 V^(-1) for 10 nm device and 28.3 V^(-1) for 5 nm device)at zero bias,surpassing the thermal voltage limit of conventional Schottky diodes,and low turn-on voltage(V_(on))of approximately 100 mV for both devices,making them ideal for power conversion applications.Using technology computer-aided design(TCAD)simulations,the observed asymmetry in electronic transport is attributed to the transition between Fowler-Nordheim tunneling(FNT)and trap-assisted tunneling(TAT)under different biasing conditions,as illustrated by the corresponding energy band profiles.Furthermore,by integrating the FTDs,a rectifier bridge circuit is designed and exhibits full-wave rectification behavior,validated through SPICE simulations for THz-band operations.This advancement offers a highly efficient solution for THz-band energy conversion and effective detection applications.
文摘AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layers(EBLs).To overcome these limitations,we propose an EBL-free DUV LD design incor-porating a 1-nm undoped Al_(0.8)Ga_(0.2)N thin strip layer after the last quantum barrier.Using PICS3D simula-tions,we evaluate the optical and electrical characteristics.Results show a significant increase in effective electron barrier height(from 158.2 meV to 420.7 meV)and a reduction in hole barrier height(from 149.2 meV to 62.8 meV),which enhance hole injection and reduce electron leakage.The optimized structure(LD3)achieves a 14%increase in output power,improved slope efficiency(1.85 W/A),and lower threshold current.This design also reduces the quantum confined Stark effect and forms dual hole accumulation regions,im-proving recombination efficiency.
基金supported by the Advanced Talents Incubation Program of Hebei University(No.521100224235)the National Natural Science Foundation of China(No.52503363)the Natural Science Foundation of Hebei Province(No.E2025201009)。
文摘Metal halide perovskites have emerged as highly promising candidates for the emissive layer in next-generation light-emitting diodes(LEDs)due to their narrow emission linewidths,high photoluminescence quantum yields,and tunable emission wavelengths.Achieving high-performance perovskite LEDs(Pe LEDs)requires the emissive layer to possess efficient radiative recombination,low defect density,minimal ion mobility,and effective carrier confinement.Perovskite/perovskite heterostructure(PPHS)offers a compelling approach for engineering emissive layers with these desired attributes,owing to their ability to passivate surface defects,tailor bandgaps,and suppress ion migration.Pe LEDs based on PPHS have demonstrated superior performance compared to single-phase devices,particularly in terms of external quantum efficiency and operational stability.This review provides a comprehensive overview of the typical PPHS architectures applied in Pe LEDs,including vertical,lateral,and bulk configurations.We discuss representative fabrication strategies and the associated optoelectronic properties of these heterostructures,highlighting the mechanisms by which they enhance device efficiency and stability.Finally,we explore the remaining challenges and prospects for the application of PPHS in Pe LEDs and other luminescent technologies.
基金supported in part by the National Key Research and Development Program of China(Grant No.2021YFC2203400)Key Laboratory Construction Project of Nanchang(Grant No.2020-NCZDSY-008)+1 种基金Jiangxi Province Double Thousand Plan (Grant No. S2019CQKJ2638)in part the National Natural Science Foundation of China(Grant Nos.62074053).
文摘This study presents aβ-Ga_(2)O_(3)diode featuring a Fin-channel structure and an anode ohmic contact.The device turnoff is facilitated by the depletion effect induced by the work function difference between the sidewall metal andβ-Ga_(2)O_(3).As the forward bias increases,electron accumulation occurs on the Fin-channel sidewalls,reducing the on-resistance and improving the forward characteristics.Moreover,the device exhibits the reduced surface field(RESURF)effect,similar to trench schottky barrier diodes(SBDs),which shifts the electric field at the fin corners and enhances the breakdown voltage.For a device with a 100 nm fin width(W_(fin)),we achieved a breakdown voltage(BV)of 1137 V,a specific on-resistance(R_(on,sp))of 1.8 mΩ·cm^(2),and a power figure of merit(PFOM)of 0.72 GW/cm^(2).This work expands the fabrication approach forβ-Ga_(2)O_(3)-based devices,advancing their potential for high-performance applications.
基金supported by 14th Five-Year Plan Key R&D Plan,Ministry of Science and Technology of the People’s Republic of China,2024YFB3409002National Natural Science Foundation of China,12302142+4 种基金HKUSTHKUST(GZ)Collaborative Research Scheme,G035Yangcheng Scholars Research Project-Leading Talent Training Project,2024312156Guangzhou-HKUST(GZ)Joint Funding Scheme,2023A03J0157Guangzhou Basic and Applied Basic Research Project,2024A04J4765Shenzhen Basic Research Project,JCYJ20220530114417040。
文摘Owing to the exceptional optoelectronic properties,metal halide perovskites have emerged as leading semiconductor materials for next-generation display technologies,providing perovskite light-emitting diodes(Pe LEDs)great potential for high-quality color displays with a wide color gamut and pure color emission.Although laboratory-scale Pe LEDs have achieved neartheoretical efficiencies,challenges such as achieving uniform large-area films,improving material stability,and enhancing patterning precision remain barriers to commercialization.This review presents a systematic analysis of scalable manufacturing and precision patterning strategies for Pe LEDs,focusing on their applications in large-area lighting and full-color displays.Fabrication methods are categorized into film deposition techniques(spin-coating,blade-coating,and thermal evaporation)and patterning strategies,including top-down(photolithography,laser/e-beam lithography,and nanoimprinting)and bottom-up(patterned crystal growth,inkjet printing,and electrohydrodynamic jet printing)approaches.In this review,we discuss the advantages and limitations of each strategy,highlight current challenges,and outlook possible pathways towards scalable,high-performance Pe LEDs for advanced optoelectronic applications.
基金supported by the National Key R&D Program of China(No.2020YFA0714604)the Fund of Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates(No.2023B1212060003)+1 种基金the SSL Sci-tech Commissioner Program(No.20234383-01KCJ-G)the National Natural Science Foundation of China(No.92463310)。
文摘Electrodeposited organic light-emitting diode(OLED)technology requires a spin-coating-free hole-injection layer that simultaneously provides smooth surface morphology,stable energy levels,and compatibility with high-resolution pixel architectures.In this study,electropolymerization of 3,4-ethylenedioxythiophene(EDOT)in poly(styrene sulfonate)(PSS-)surfactant-solubilized colloidal media is shown to afford poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)films with robust surface uniformity and stable energy levels suitable for application as hole-injection layers in OLEDs.Systematic investigation reveals that the hole-injection properties of these films are governed primarily by the colloidal chemistry of EDOT/PSS-surfactant-solubilized systems,rather than by conventional electrochemical parameters.This colloidal regulation modulates the film work function over a practically useful range.Incorporation of optimized films into OLEDs leads to enhanced hole injection and improved device performance,with external quantum efficiency increasing from 2.2%to 7.4%and minimal roll-off.Overall,this work demonstrates a feasible example of realizing spin-coating-free hole-injection layers,offering a potential direction for the development of electrodeposited injection layers for OLEDs.
基金the support from the Jiangsu Provincial Senior Talent Program (Dengfeng,Jiangsu University)the support from the National Key R&D Program of China (No.2024YFB3612600)+3 种基金the National Natural Science Foundation of China (Nos.22275098,62288102)Basic Research Program of Jiangsu (No.BK20243057)the Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications (No.NY222097)the National Natural Science Foundation of China (No.62205035)。
文摘To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics.
基金supported by the Natural Science Foundation of Jiangsu Province(Grant.BK20232042).
文摘Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LEDs[7,8].However,it took much longer time for GaN-based LDs to achieve high power,high wall plug efficiency,and long lifetime.Until 2019,Nichia reported blue LDs with these performances[9],which open wide applications with GaN-based blue LDs.
文摘Perovskite quantum dot light-emitting diodes(Pe-QLEDs)have shown immense application potential in display and lighting fields due to their narrow full-width at half maximum(FWHM)and high photoluminescence quantum yield(PLQY).Despite significant advancements in their performance,challenges such as defects and ion migration still hinder their long-term stability and operational efficiency.To address these issues,various optimization strategies,including ligand engineering,interface passivation,and self-assembly strategy,are being actively researched.This review focuses on the synthesis methods,challenges and optimization of perovskite quantum dots,which are critical for the commercialization and large-scale production of high-performance and stable Pe-QLEDs.
文摘Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hinder system integration due to their specific manufacturing processes.Conversely,metal oxide diodes,with their simple fabrication techniques,offer advantages for system integration.The oxygen vacancy defect of oxide semiconductor will greatly affect the electrical performance of the device,so the performance of the diode can be effectively controlled by adjusting the oxygen vacancy concentration.This study centers on optimizing the performance of diodes by modulating the oxygen vacancy concentration within InGaZnO films through control of oxygen flows during the sputtering process.Experimental results demonstrate that the diode exhibits a forward current density of 43.82 A·cm^(−2),with a rectification ratio of 6.94×10^(4),efficiently rectifying input sine signals with 1 kHz frequency and 5 V magnitude.These results demonstrate its potential in energy conversion and management.By adjusting the oxygen vacancy,a methodology is provided for optimizing the performance of rectifying diodes.
基金support from the National Key Research and Development Program of China(2024YFA1207700)National Natural Science Foundation of China(52072141,52102170).
文摘The quantum confinement effect fundamentally alters the optical and electronic properties of quantum dots(QDs),making them versatile building blocks for next-generation light-emitting diodes(LEDs).This study investigates how quantum confinement governs the charge transport,exciton dynamics,and emission efficiency in QD-LEDs,using CsPbI_(3) QDs as a model system.By systematically varying QD sizes,we reveal size-dependent trade-offs in LED performance,such as enhanced efficiency for smaller QDs but increased brightness and stability for larger QDs under high current densities.Our findings offer critical insights into the design of high-performance QD-LEDs,paving the way for scalable and energy-efficient optoelectronic devices.
文摘There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.
基金supported by the National Natural Science Foundation of China(Grant No.12174051)the Fundamental Research Funds for Central Universities。
文摘We investigate the possible Josephson diode effect(JDE)in a two-dimensional(2D)nonmagnetic planar s-wave superconductor junction,which is constructed on a spin-collinear d-wave altermagnet(AM)material in the presence of Rashba spin-orbit interaction.It is demonstrated that the JDE is critically dependent on the crystalline axis of the AM relative to the current direction.The d_(x^(2)-y^(2))magnetization symmetry can support a JDE whereas the dxy symmetry does not facilitate it.The JDE efficiency can reach up to 40%and can be adjusted by an additional asymmetric gate voltage applied to the non-superconducting region of the junction,including control of its polarity.Our findings provide an electrical means to control the JDE within a non-magnetic AM-based superconducting junction.
基金supported via funding from Prince Sattam Bin Abdulaziz University project number(PSAU/2025/R/1446).
文摘Promoting the high penetration of renewable energies like photovoltaic(PV)systems has become an urgent issue for expanding modern power grids and has accomplished several challenges compared to existing distribution grids.This study measures the effectiveness of the Puma optimizer(PO)algorithm in parameter estimation of PSC(perovskite solar cells)dynamic models with hysteresis consideration considering the electric field effects on operation.The models used in this study will incorporate hysteresis effects to capture the time-dependent behavior of PSCs accurately.The PO optimizes the proposed modified triple diode model(TDM)with a variable voltage capacitor and resistances(VVCARs)considering the hysteresis behavior.The suggested PO algorithm contrasts with other wellknown optimizers from the literature to demonstrate its superiority.The results emphasize that the PO realizes a lower RMSE(Root mean square errors),which proves its capability and efficacy in parameter extraction for the models.The statistical results emphasize the efficiency and supremacy of the proposed PO compared to the other well-known competing optimizers.The convergence rates show good,fast,and stable convergence rates with lower RMSE via PO compared to the other five competitive optimizers.Moreover,the lowermean realized via the PO optimizer is illustrated by the box plot for all optimizers.
基金the financial support of the National Natural Science Foundation of China(No.22205165).
文摘Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting the chemical potential of moisture into electric energy through interactions with hygroscopic materials and nanostructured interfaces.Unlike solar or thermal harvesters,MEGs operate continuously by utilizing ubiquitous atmospheric moisture,granting them unique spatial and temporal adaptability.Despite nearly a decade of progress and the exploration of diverse material systems for MEG,the overall output power remains significantly limited due to inherently low charge carrier concentrations and restricted ion diffusion fluxes[2].As a result,standalone MEG devices often deliver low and unstable output,limiting practical applications.To enhance performance and versatility,recent efforts have explored hybridization of MEG with other ambient energy sources such as triboelectric or thermoelectric effects.
基金supported by the Research Projects of Department of Education of Guangdong Province-024CJPT002Special Project of Guangdong Provincial Department of Education in Key Areas (No. 6021210075K)Shenzhen Polytechnic University Research Fund. (No. 6024310006K)
文摘Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancements have been made in the performance of cadmium-free QLEDs.However,several challenges persist in the industrialization of ecofriendly QLED displays.For instance,(1)the poor performance,characterized by low photoluminescence quantum yield(PLQY),unstable ligand,and charge imbalance,cannot be effectively addressed with a solitary strategy;(2)the degradation mechanism,involving emission quenching,morphological inhomogeneity,and field-enhanced electron delocalization remains unclear;(3)the lack of techniques for color patterning,such as optical lithography and transfer printing.Herein,we undertake a specific review of all technological breakthroughs that endeavor to tackle the above challenges associated with cadmium-free QLED displays.We begin by reviewing the evolution,architecture,and operational characteristics of eco-friendly QLEDs,highlighting the photoelectric properties of QDs,carrier transport layer stability,and device lifetime.Subsequently,we focus our attention not only on the latest insights into device degradation mechanisms,particularly,but also on the remarkable technological progress in color patterning techniques.To conclude,we provide a synthesis of the promising prospects,current challenges,potential solutions,and emerging research trends for QLED displays.
基金supported by the National Natural Science Foundation of China(Nos.22205058,22105064,52122308)the Funding Plan of Key Scientific Research Projects in Colleges and Universities of Henan Province(No.23A150001)+2 种基金Doctoral Scientific Research Start-up Foundation from Henan University of Technology(No.2021BS024)the Project of Youth Backbone Teachers of Henan University of Technology(No.21421250)the Innovative Funds Plan of Henan University of Technology(No.2022ZKCJ01)。
文摘Carbon dots(CDs),due to their low cost,high stability,and high luminous efficiency,have emerged as an excellent material for the emissive layer in next-generation electroluminescent light-emitting diodes(ELEDs).However,improving the efficiency of fluorescent CDs-based ELEDs remains challenging,primarily because it is difficult to utilize triplet excitons in the electroluminescence process.Therefore,enhancing the exciton utilization efficiency of CDs during electroluminescence is crucial.Based on this,we exploited the characteristic large exciton binding energy commonly found in CDs to develop exciton-emitting CDs.These CDs facilitate the radiative recombination of excitons during electroluminescence,thereby improving the electroluminescent efficiency.By rationally selecting precursors,we developed high quantum efficiency CDs and subsequently constructed CDs-based ELEDs.The blue-light device exhibited an external quantum efficiency of over 4%.This study introduces a novel design concept for CDs,providing a new strategy for developing high-performance blue ELEDs based on CDs.
基金support from MATRIX(ANR-22-CE92-0047)with financial support from ITMI Cancer of Aviesan within the framework of the 2021−2030 Cancer Control Strategy,on funds administrated by INSERM through the project NECTAR.Matilde Siviero acknowledges funding from the French−German University/Saarbrücken(contract CDOC-06-2022).
文摘GaN diodes for high energy(64.8 MeV)proton detection were fabricated and investigated.A comparison of the performance of GaN diodes with different structures is presented,with a focus on sapphire and on GaN substrates,Schottky and pin diodes,and different active layer thicknesses.Pin diodes fabricated on a sapphire substrate are the best choice for a GaN proton detector working at 0 V bias.They are sensitive(minimum detectable proton beam<1 pA/cm^(2)),linear as a function of proton current and fast(<1 s).High proton current sensitivity and high spatial resolution of GaN diodes can be exploited in the future for proton imaging of patients in proton therapy.
文摘Background Plant tissue culture has emerged as a tool for improving cotton propagation and genetics,but recalcitrance nature of cotton makes it difficult to develop in vitro regeneration.Cotton’s recalcitrance is influenced by genotype,explant type,and environmental conditions.To overcome these issues,this study uses different machine learning-based predictive models by employing multiple input factors.Cotyledonary node explants of two commercial cotton cultivars(STN-468 and GSN-12)were isolated from 7–8 days old seedlings,preconditioned with 5,10,and 20 mg·L^(-1) kinetin(KIN)for 10 days.Thereafter,explants were postconditioned on full Murashige and Skoog(MS),1/2MS,1/4MS,and full MS+0.05 mg·L^(-1) KIN,cultured in growth room enlightened with red and blue light-emitting diodes(LED)combination.Statistical analysis(analysis of variance,regression analysis)was employed to assess the impact of different treatments on shoot regeneration,with artificial intelligence(AI)models used for confirming the findings.Results GSN-12 exhibited superior shoot regeneration potential compared with STN-468,with an average of 4.99 shoots per explant versus 3.97.Optimal results were achieved with 5 mg·L^(-1) KIN preconditioning,1/4MS postconditioning,and 80%red LED,with maximum of 7.75 shoot count for GSN-12 under these conditions;while STN-468 reached 6.00 shoots under the conditions of 10 mg·L^(-1) KIN preconditioning,MS with 0.05 mg·L^(-1) KIN(postconditioning)and 75.0%red LED.Rooting was successfully achieved with naphthalene acetic acid and activated charcoal.Additionally,three different powerful AI-based models,namely,extreme gradient boost(XGBoost),random forest(RF),and the artificial neural network-based multilayer perceptron(MLP)regression models validated the findings.Conclusion GSN-12 outperformed STN-468 with optimal results from 5 mg·L^(-1) KIN+1/4MS+80%red LED.Application of machine learning-based prediction models to optimize cotton tissue culture protocols for shoot regeneration is helpful to improve cotton regeneration efficiency.
