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Simulation of Diode-Pumped Q-Switched Nd:YAG Laser Generating Eye-Safe Signal in IOPO Environment
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作者 Mian M. Ashraf Muhammad Siddique 《Optics and Photonics Journal》 2012年第3期167-172,共6页
Numerical simulation of diode-pumped Q-switched Nd:YAG laser leading to the generation of eye-safe signal in singly resonant Intracavity Optical Parametric Oscillator (IOPO) is presented. Starting from rate equations,... Numerical simulation of diode-pumped Q-switched Nd:YAG laser leading to the generation of eye-safe signal in singly resonant Intracavity Optical Parametric Oscillator (IOPO) is presented. Starting from rate equations, the time dependent laser equations have been solved numerically, whereas the space-dependent OPO equations analytically. Our results show that 1.4 J diode laser (810 nm) pulse with 200 msec width, delivers 30 mJ Nd:YAG laser (1064 nm) pulse with 5 n-second width. This Nd:YAG laser further generates 9 mJ eye safe signal (1570 nm) pulse with 2.5 n-second width. 展开更多
关键词 SIMULATION diode LASER Q-SWITCHED Nd:YAG LASER Eye-Safe LASER SIGNAL Idler IOPO Rate Equations Out-Put Power KTP Non-Linear Crystal Pump Beam WAIST
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Reduction of Electron Leakage in a Deep Ultraviolet Nitride Laser Diode with a Double-Tapered Electron Blocking Layer 被引量:3
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作者 Yi-Fu Wang Mussaab I.Niass +1 位作者 Fang Wang Yu-Huai Liu 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第5期67-70,共4页
A double-tapered AlGaN electron blocking layer (EBL) is proposed to apply in a deep ultraviolet semiconductor laser diode. Compared with the inverse double-tapered EBL, the laser with the double-tapered EBL shows a hi... A double-tapered AlGaN electron blocking layer (EBL) is proposed to apply in a deep ultraviolet semiconductor laser diode. Compared with the inverse double-tapered EBL, the laser with the double-tapered EBL shows a higher slope efficiency, which indicates that effective enhancement in the transportation of electrons and holes is achieved. Particularly, comparisons among the double-tapered EBL, the inverse double-tapered EBL, the singletapered EBL and the inverse single-tapered EBL show that the double-tapered EBL has the best performance in terms of current leakage. 展开更多
关键词 EBL AlGaN REDUCTION of ELECTRON Leakage in a Deep Ultraviolet NITRIDE Laser diode with a Double-Tapered ELECTRON Blocking Layer
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Diode Pumped High Peak Power Quasi Q-Switched and Passively Q-Switched Nd:YVO<sub>4</sub>Lasers at 1064 nm and 532 nm using Cr:YAG and KTP crystals
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作者 Ashraf F. El-Sherif Mahmoud M. Talat 《Optics and Photonics Journal》 2013年第1期51-62,共12页
Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designati... Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designation systems. In this paper we presents theoretical calculations using Advanced Dynamics Professional LASCAD software and experimental studies for a high power pigtailed fiber diode laser module of 8 W operating at 808 nm with a specially designed high efficiency cooling system, end pumped high-efficiency Nd:YVO4 laser of 3 × 3 × 10 mm rod and overall cavity length of 44 mm. To the best of our knowledge a self Q-switching effects was generated in Nd:YVO4 laser by changing the cavity dimensions and the position of the intracavity KTP crystal at certain regime of operation for the first time, in which the cavity length is reduced to be 30 mm and the distance between Nd:YVO4 rod and KTP crystal is only 1mm. Self Q-switched laser pulse at 532 nm with high peak power of 96 W, pulse width of 88 ns at FWHM and repetition rate of 400 kHz was achieved. Experimental studies of a passive Q-switched Nd:YVO4 laser using Cr:YAG crystal with three different transmissions of 30%, 40% and 70% were investigated. Passive Q-switched laser pulse at 1064 nm and narrow line width of less than 1.5 nm with highest peak power of nearly 18 kW, short pulse width of less than 4 ns at FWHM and higher repetition rate of 45 kHz using Cr:YAG with transmission of 30% was achieved for the first time. 展开更多
关键词 High POWER diode LASER High POWER Nd:YVO4 LASER CR:YAG Saturable Absorber Mirror Passive Q-SWITCHING KTP Crystal Self Q-SWITCHING Special Cooling System
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Wettability Gradient-Induced Diode:MXene-Engineered Membrane for Passive-Evaporative Cooling 被引量:1
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作者 Leqi Lei Shuo Meng +4 位作者 Yifan Si Shuo Shi Hanbai Wu Jieqiong Yang Jinlian Hu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期382-397,共16页
Thermoregulatory textiles,leveraging high-emissivity structural materials,have arisen as a promising candidate for personal cooling management;however,their advancement has been hindered by the underperformed water mo... Thermoregulatory textiles,leveraging high-emissivity structural materials,have arisen as a promising candidate for personal cooling management;however,their advancement has been hindered by the underperformed water moisture transportation capacity,which impacts on their thermophysiological comfort.Herein,we designed a wettability-gradient-induced-diode(WGID)membrane achieving by MXene-engineered electrospun technology,which could facilitate heat dissipation and moisture-wicking transportation.As a result,the obtained WGID membrane could obtain a cooling temperature of 1.5℃ in the“dry”state,and 7.1℃ in the“wet”state,which was ascribed to its high emissivity of 96.40%in the MIR range,superior thermal conductivity of 0.3349 W m^(-1) K^(-1)(based on radiation-and conduction-controlled mechanisms),and unidirectional moisture transportation property.The proposed design offers an approach for meticulously engineering electrospun membranes with enhanced heat dissipation and moisture transportation,thereby paving the way for developing more efficient and comfortable thermoregulatory textiles in a high-humidity microenvironment. 展开更多
关键词 Passive-evaporative cooling MXene Electrospun membrane Wettability gradient diode
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Growth,leaf anatomy,and photosynthesis of cotton(Gossypium hirsutum L.)seedlings in response to four light-emitting diodes and high pressure sodium lamp 被引量:1
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作者 ZHANG Yichi LIAO Baopeng +3 位作者 LI Fangjun ENEJI AEgrinya DU Mingwei TIAN Xiaoli 《Journal of Cotton Research》 CAS 2024年第1期79-89,共11页
Background Light is a critical factor in plant growth and development,particularly in controlled environments.Light-emitting diodes(LEDs)have become a reliable alternative to conventional high pressure sodium(HSP)lamp... Background Light is a critical factor in plant growth and development,particularly in controlled environments.Light-emitting diodes(LEDs)have become a reliable alternative to conventional high pressure sodium(HSP)lamps because they are more efficient and versatile in light sources.In contrast to well-known specialized LED light spectra for vegetables,the appropriate LED lights for crops such as cotton remain unknown.Results In this growth chamber study,we selected and compared four LED lights with varying percentages(26.44%–68.68%)of red light(R,600–700 nm),combined with other lights,for their effects on growth,leaf anatomy,and photosynthesis of cotton seedlings,using HSP lamp as a control.The total photosynthetic photon flux density(PPFD)was(215±2)μmol·m-2·s-1 for all LEDs and HSP lamp.The results showed significant differences in all tested parameters among lights,and the percentage of far red(FR,701–780 nm)within the range of 3.03%–11.86%was positively correlated with plant growth(characterized by leaf number and area,plant height,stem diameter,and total biomass),palisade layer thickness,photosynthesis rate(Pn),and stomatal conductance(Gs).The ratio of R/FR(4.445–11.497)negatively influenced the growth of cotton seedlings,and blue light(B)suppressed stem elongation but increased palisade cell length,chlorophyll content,and Pn.Conclusion The LED 2 was superior to other LED lights and HSP lamp.It had the highest ratio of FR within the total PPFD(11.86%)and the lowest ratio of R/FR(4.445).LED 2 may therefore be used to replace HPS lamp under controlled environments for the study of cotton at the seedling stage. 展开更多
关键词 Cotton seedling Light-emitting diodes BIOMASS Palisade cell PHOTOSYNTHESIS
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Recent Advances in Patterning Strategies for Full‑Color Perovskite Light‑Emitting Diodes
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作者 Gwang Heon Lee Kiwook Kim +2 位作者 Yunho Kim Jiwoong Yang Moon Kee Choi 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期99-137,共39页
Metal halide perovskites have emerged as promising light-emitting materials for next-generation displays owing to their remarkable material characteristics including broad color tunability,pure color emission with rem... Metal halide perovskites have emerged as promising light-emitting materials for next-generation displays owing to their remarkable material characteristics including broad color tunability,pure color emission with remarkably narrow bandwidths,high quantum yield,and solution processability.Despite recent advances have pushed the luminance efficiency of monochromic perovskite light-emitting diodes(PeLEDs)to their theoretical limits,their current fabrication using the spincoating process poses limitations for fabrication of full-color displays.To integrate PeLEDs into full-color display panels,it is crucial to pattern red–green–blue(RGB)perovskite pixels,while mitigating issues such as cross-contamination and reductions in luminous efficiency.Herein,we present state-of-the-art patterning technologies for the development of full-color PeLEDs.First,we highlight recent advances in the development of efficient PeLEDs.Second,we discuss various patterning techniques of MPHs(i.e.,photolithography,inkjet printing,electron beam lithography and laserassisted lithography,electrohydrodynamic jet printing,thermal evaporation,and transfer printing)for fabrication of RGB pixelated displays.These patterning techniques can be classified into two distinct approaches:in situ crystallization patterning using perovskite precursors and patterning of colloidal perovskite nanocrystals.This review highlights advancements and limitations in patterning techniques for PeLEDs,paving the way for integrating PeLEDs into full-color panels. 展开更多
关键词 PEROVSKITE Light-emitting diode Full-color display High-resolution patterning ELECTROLUMINESCENCE
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Flexible planar micro supercapacitor diode
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作者 Yihui Ma Pei Tang +7 位作者 Zhenyuan Miao Wuyang Tan Qijun Wang Yuecong Chen Guosheng Li Qingyun Dou Xingbin Yan Lingling Shui 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期429-435,I0011,共8页
Supercapacitor diode is a novel ion device that performs both supercapacitor energy storage and ion diode rectification functions.However,previously reported devices are limited by their large size and complex process... Supercapacitor diode is a novel ion device that performs both supercapacitor energy storage and ion diode rectification functions.However,previously reported devices are limited by their large size and complex processes.In this work,we demonstrate a screen-printed micro supercapacitor diode(MCAPode)that based on the insertion of a finger mode with spinel ZnCo_(2)O_(4) as cathode and activated carbon as anode for the first time,and featuring an excellent area specific capacitance(1.21 mF cm^(-2)at 10 mV s^(-1))and high rectification characteristics(rectification ratioⅠof 11.99 at 40 mV s^(-1)).Taking advantage of the ionic gel electrolyte,which provides excellent stability during repeated flexing and at high temperatures.In addition,MCAPode exhibits excellent electrochemical performance and rectification capability in"AND"and"OR"logic gates.These findings provide practical solutions for future expansion of micro supercapacitor diode applications. 展开更多
关键词 Micro devices Supercapacitor diodes Screen-printing RECTIFICATION Logic gates
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Effect of annealing on the electrical performance of N-polarity GaN Schottky barrier diodes
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作者 Nuo Xu Gaoqiang Deng +6 位作者 Haotian Ma Shixu Yang Yunfei Niu Jiaqi Yu Yusen Wang Jingkai Zhao Yuantao Zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期48-55,共8页
A nitrogen-polarity(N-polarity)GaN-based high electron mobility transistor(HEMT)shows great potential for high-fre-quency solid-state power amplifier applications because its two-dimensional electron gas(2DEG)density ... A nitrogen-polarity(N-polarity)GaN-based high electron mobility transistor(HEMT)shows great potential for high-fre-quency solid-state power amplifier applications because its two-dimensional electron gas(2DEG)density and mobility are mini-mally affected by device scaling.However,the Schottky barrier height(SBH)of N-polarity GaN is low.This leads to a large gate leakage in N-polarity GaN-based HEMTs.In this work,we investigate the effect of annealing on the electrical characteristics of N-polarity GaN-based Schottky barrier diodes(SBDs)with Ni/Au electrodes.Our results show that the annealing time and tem-perature have a large influence on the electrical properties of N-polarity GaN SBDs.Compared to the N-polarity SBD without annealing,the SBH and rectification ratio at±5 V of the SBD are increased from 0.51 eV and 30 to 0.77 eV and 7700,respec-tively,and the ideal factor of the SBD is decreased from 1.66 to 1.54 after an optimized annealing process.Our analysis results suggest that the improvement of the electrical properties of SBDs after annealing is mainly due to the reduction of the inter-face state density between Schottky contact metals and N-polarity GaN and the increase of barrier height for the electron emis-sion from the trap state at low reverse bias. 展开更多
关键词 nitrogen polarity GAN Schottky barrier diodes ANNEALING interface state
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Flexible perovskite light-emitting diodes for display applications and beyond
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作者 Yongqi Zhang Shahbaz Ahmed Khan +1 位作者 Dongxiang Luo Guijun Li 《Journal of Semiconductors》 EI CAS CSCD 2024年第5期8-25,共18页
The flexible perovskite light-emitting diodes(FPeLEDs),which can be expediently integrated to portable and wearable devices,have shown great potential in various applications.The FPeLEDs inherit the unique optical pro... The flexible perovskite light-emitting diodes(FPeLEDs),which can be expediently integrated to portable and wearable devices,have shown great potential in various applications.The FPeLEDs inherit the unique optical properties of metal halide perovskites,such as tunable bandgap,narrow emission linewidth,high photoluminescence quantum yield,and particularly,the soft nature of lattice.At present,substantial efforts have been made for FPeLEDs with encouraging external quantum efficiency(EQE)of 24.5%.Herein,we summarize the recent progress in FPeLEDs,focusing on the strategy developed for perovskite emission layers and flexible electrodes to facilitate the optoelectrical and mechanical performance.In addition,we present relevant applications of FPeLEDs in displays and beyond.Finally,perspective toward the future development and applications of flexible PeLEDs are also discussed. 展开更多
关键词 metal halide perovskite flexible light-emitting diodes optical properties mechanical flexibility DISPLAY
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Highly Efficient Greenish-Yellow Phosphorescent Organic Light-Emitting Diodes Based on a Novel 2,3-Diphenylimidazo[1,2-a]Pyridine Iridium(Ⅲ) Complex 被引量:1
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作者 孙军 席敏 +6 位作者 苏子生 何海晓 田密 李红燕 张宏科 毛涛 张玉祥 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期127-130,共4页
A cyclometalated greenish-yellow emitter 2,3-diphenylimidazo[1,2-a]pyridine iridium(Ill) complex is successfully synthesized and used to fabricate phosphorescent organic light-emitting diodes. The optimized device e... A cyclometalated greenish-yellow emitter 2,3-diphenylimidazo[1,2-a]pyridine iridium(Ill) complex is successfully synthesized and used to fabricate phosphorescent organic light-emitting diodes. The optimized device exhibits a greenish-yellow emission with the peak at 523nm and a strong shoulder at 557nm, corresponding to Commission Internationale de l'Eclairage coordinates of (0.38, 0.68). The full width at half maximum of the device is 93 nm, which is broader than the fac-tris(2-phenylpyridine)iridium [Ir(ppy)3] based reference device of 78 nm. Meanwhile, a maximum current efficiency of 62.6 cd/A (47.51m/W) is obtained. This result is higher than a maximum current efficiency of 54.8 cd/A (431m/W) of the Ir(ppy)a based device. The results indicate that this new iridium complex may have potential applications in fabricating high color rendering index white organic light emitting diodes. 展开更多
关键词 of OLEDs Complex Highly Efficient Greenish-Yellow Phosphorescent Organic Light-Emitting diodes Based on a Novel 2 3-Diphenylimidazo[1 2-a]Pyridine Iridium in EML than high nm that were CRI LUMO is on
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The Influence of Ultrasonic Treatment on the Properties of Schottky Diodes
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作者 I. G. Pashayev 《Open Journal of Acoustics》 2013年第3期9-12,共4页
The given work studies the reason of the change of a superfluous current near crystallization temperature of an amorphous αPbSb metal alloy and at the same time founds out the influence of ultrasonic processing (USP)... The given work studies the reason of the change of a superfluous current near crystallization temperature of an amorphous αPbSb metal alloy and at the same time founds out the influence of ultrasonic processing (USP) on the properties of αPbSb-nSi solar elements (SE), made by Shottki diodes technology (ShD) with a metal alloy. It is found that occurrence of a superfluous current αPbSb-nSi ShD under the influence of thermoannealing is connected with changes of structure of an amorphous film of metal at transition in a polycrystalline condition. VAC damaged αPbSb-nSi Sh Dare very sensitive to annealing time. Eventually, even at room temperature, level of a superfluous current decreases, i.e. “the wound” put by mechanical damage sort of heals, restoration process occurs the faster, the higher the annealing temperature is. Function of γt annealing parameters changes in an interval and the influence USP on photo-electric properties αPbSb-nSi SE depends on the chosen UIT mode. 展开更多
关键词 PHOTOSENSITIVITY BARRIER Properties AMORPHOUS Metals diodeS Shottki Superfluous CURRENTS Degradations Ultrasonic Influence Silicon Solar Elements
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Design,preparation,and characterization of a novel ZnO/CuO/Al energetic diode with dual functionality:Logic and destruction
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作者 Jialu Yang Jiaheng Hu +3 位作者 Yinghua Ye Jianbing Xu Yan Hu Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期57-68,共12页
Self-destructing chips have promising applications for securing data.This paper proposes a new concept of energetic diodes for the first time,which can be used for self-destructive chips.A simple two-step electrochemi... Self-destructing chips have promising applications for securing data.This paper proposes a new concept of energetic diodes for the first time,which can be used for self-destructive chips.A simple two-step electrochemical deposition method is used to prepare ZnO/CuO/Al energetic diode,in which N-type ZnO and P-type CuO are constricted to a PN junction.This paper comprehensively discusses the material properties,morphology,semiconductor characteristics,and exploding performances of the energetic diode.Experimental results show that the energetic diode has typical rectification with a turn-on voltage of about 1.78 V and a reverse leakage current of about 3×10^(-4)A.When a constant voltage of 70 V loads to the energetic diode in the forward direction for about 0.14 s or 55 V loads in the reverse direction for about 0.17 s,the loaded power can excite the energetic diode exploding and the current rises to about100 A.Due to the unique performance of the energetic diode,it has a double function of rectification and explosion.The energetic diode can be used as a logic element in the normal chip to complete the regular operation,and it can release energy to destroy the chip accurately. 展开更多
关键词 Energetic diode ZnOCuOAl thermite ZnO/CuO PN junction Electrical explosion performance Self-destructing chips
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Physico−mathematical model of the voltage−current characteristics of light-emitting diodes with quantum wells based on the Sah−Noyce−Shockley recombination mechanism
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作者 Fedor I.Manyakhin Dmitry O.Varlamov +3 位作者 Vladimir P.Krylov Lyudmila O.Morketsova Arkady A.Skvortsov Vladimir K.Nikolaev 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期25-33,共9页
Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS reco... Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their adequacy.The technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4. 展开更多
关键词 light-emitting diodes with quantum wells voltagecurrent relation nonideality factor recombination mechanism SahNoyceShockley model
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High-Sensitivity Ozone Sensing Using 280 nm Deep Ultraviolet Light-Emitting Diode for Detection of Natural Hazard Ozone 被引量:1
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作者 Yoshinobu Aoyagi Misaichi Takeuchi +6 位作者 Kaoru Yoshida Masahito Kurouchi Tsutomu Araki Yasushi Nanishi Hiroyasi Sugano Yumi Ahiko Hirotaka Nakamura 《Journal of Environmental Protection》 2012年第8期695-699,共5页
Recently ozone is one of natural hazards which comes from cars, industry using ozone for sterilization of organic and inorganic materials and for water purification. So, ozone sensing becomes very important, and conve... Recently ozone is one of natural hazards which comes from cars, industry using ozone for sterilization of organic and inorganic materials and for water purification. So, ozone sensing becomes very important, and convenient and accurate ozone sensor is required. A new high sensitivity ozone sensing system using an deep ultra-violet light emitting diode (DUV-LED) operated at the wavelength of 280 nm has been successfully constructed. The fabrication of diode operated at 280 nm is much easier than that of DUV-LED operated at Hg lamp wavelength of 254 nm. The system is compact and possible to sense the ozone concentration less than 0.1 ppm with an accuracy of 0.5% easily with low power DUV-LED of around 200 micro Watts operated at 280 nm without any data processing circuit. 展开更多
关键词 OZONE SENSING Deep Ultra VIOLET Light EMITTING diode DUV-LED High Sensitivity Long Life Compact
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Proton‑Prompted Ligand Exchange to Achieve High‑Efficiency CsPbI_(3) Quantum Dot Light‑Emitting Diodes 被引量:1
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作者 Yanming Li Ming Deng +2 位作者 Xuanyu Zhang Lei Qian Chaoyu Xiang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期53-62,共10页
CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting diodes.However,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improv... CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting diodes.However,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improvement of device performance.Traditional in-situ ligand replacement and ligand exchange after synthesis were often difficult to control.Here,we proposed a new ligand exchange strategy using a proton-prompted insitu exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI_(3)QDs.This exchange strategy maintained the size and morphology of CsPbI_(3)QDs and improved the optical properties and the conductivity of CsPbI_(3)QDs films.As a result,high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45%and an operational half-life of 10.79 h. 展开更多
关键词 CsPbI_(3) perovskite quantum dots Light-emitting diodes Ligand exchange Proton-prompted in-situ exchange
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Thermally annealed gamma irradiated Ni/4H-SiC Schottky barrier diode characteristics 被引量:2
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作者 P.Vigneshwara Raja N.V.L.Narasimha Murty 《Journal of Semiconductors》 EI CAS CSCD 2019年第2期57-63,共7页
Thermal annealing effects on gamma irradiated Ni/4 H-SiC Schottky barrier diode(SBD) characteristics are analyzed over a wide range of temperatures(400–1100 °C). The annealing induced variations in the concentra... Thermal annealing effects on gamma irradiated Ni/4 H-SiC Schottky barrier diode(SBD) characteristics are analyzed over a wide range of temperatures(400–1100 °C). The annealing induced variations in the concentration of deep level traps in the SBDs are identified by thermally stimulated capacitance(TSCAP). A little decrease in the trap density at E_C – 0.63 eV and E_C –1.13 eV is observed up to the annealing temperature of 600 °C. Whereas, a gamma induced trap at E_C – 0.89 eV disappeared after annealing at 500 °C, revealing that its concentration(< 1013 cm-3) is reduced below the detection limit of the TSCAP technique.The electrical characteristics of irradiated SBDs are considerably changed at each annealing temperature. To understand the anomalous variations in the post-annealing characteristics, the interface state density distribution in the annealed SBDs is extracted.The electrical properties are improved at 400 °C due to the reduction in the interface trap density. However, from 500 °C, the electrical parameters are found to degrade with the annealing temperature because of the increase in the interface trap density.From the results, it is noted that the rectifying nature of the SBDs vanishes at or above 800 °C. 展开更多
关键词 4H-silicon CARBIDE SCHOTTKY barrier diode thermal annealing electrically active defects thermally stimulated CAPACITANCE
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High-efficiency ultra-fast all-optical photonic crystal diode based on the lateral-coupled nonlinear elliptical defect
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作者 李大星 刘凯柱 +3 位作者 余春龙 张括 刘跃钦 冯帅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期453-458,共6页
An all-optical Fano-like diode featuring a nonlinear lateral elliptical micro-cavity and a reflecting column in the photonic crystal waveguide is proposed.The asymmetric micro-cavity is constructed by removing one rod... An all-optical Fano-like diode featuring a nonlinear lateral elliptical micro-cavity and a reflecting column in the photonic crystal waveguide is proposed.The asymmetric micro-cavity is constructed by removing one rod and changing the shape of the lateral rod from a circle to an ellipse.A reflecting pillar is also introduced into the waveguide to construct an F-P cavity with the elliptical defect and enhance the asymmetric transmission for the incident light wave transmitting rightwards and leftwards,respectively.By designing the size of the ellipse and optimizing a reflecting rod at a suitable position,a maximum forward light transmittance of-1.14 dB and a minimum backward transmittance of-57.66 dB are achieved at the working wavelength of 1550.47 nm.The corresponding response time is about 10 ps when the intensity of the pump light beam resonant at 637 nm is 3.97 W/μm2. 展开更多
关键词 photonic crystal all-optical diode Fano cavity unidirectional transmission
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Finely regulated luminescent Ag-In-Ga-S quantum dots with green-red dual emission toward white light-emitting diodes
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作者 Zhi Wu Leimeng Xu +1 位作者 Jindi Wang Jizhong Song 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第9期54-63,共10页
Ag-In-Ga-S(AIGS)quantum dots(QDs)have recently attracted great interests due to the outstanding optical properties and eco-friendly components,which are considered as an alternative replacement for toxic Pb-and Cd-bas... Ag-In-Ga-S(AIGS)quantum dots(QDs)have recently attracted great interests due to the outstanding optical properties and eco-friendly components,which are considered as an alternative replacement for toxic Pb-and Cd-based QDs.However,enormous attention has been paid to how to narrow their broadband spectra,ignoring the application advantages of the broadband emission.In this work,the AIGS QDs with controllable broad green-red dual-emission are first reported,which is achieved through adjusting the size distribution of QDs by controlling the nucleation and growth of AIGS crystals.Resultantly,the AIGS QDs exhibit broad dual-emission at green-and red-band evidenced by photoluminescence(PL)spectra,and the PL relative intensity and peak position can be finely adjusted.Furthermore,the dual-emission is the intrinsic characteristics from the difference in confinement effect of large particles and tiny particles confirmed by temperature-dependent PL spectra.Accordingly,the AIGS QDs(the size consists of 17 nm and 3.7 nm)with 530 nm and 630 nm emission could successfully be synthesized at 220°C.By combining the blue light-emitting diode(LED)chips and dual-emission AIGS QDs,the constructed white light-emitting devices(WLEDs)exhibit a continuous and broad spectrum like natural sunlight with the Commission Internationale de l’Eclairage(CIE)chromaticity coordinates of(0.33,0.31),a correlated color temperature(CCT)of 5425 K,color rendering index(CRI)of 90,and luminous efficacy of radiation(LER)of 129 lm/W,which indicates that the AIGS QDs have huge potential for lighting applications. 展开更多
关键词 quantum dots Ag-In-Ga-S dual emission white light-emitting diodes
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Enhancing the Performance of Perovskite Light-Emitting Diodes via Synergistic Effect of Defect Passivation and Dielectric Screening
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作者 Xuanchi Yu Jia Guo +11 位作者 Yulin Mao Chengwei Shan Fengshou Tian Bingheng Meng Zhaojin Wang Tianqi Zhang Aung Ko Ko Kyaw Shuming Chen Xiaowei Sun Kai Wang Rui Chen Guichuan Xing 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期244-256,共13页
Metal halide perovskites,particularly the quasi-two-dimensional perovskite subclass,have exhibited considerable potential for next-generation electroluminescent materials for lighting and display.Nevertheless,the pres... Metal halide perovskites,particularly the quasi-two-dimensional perovskite subclass,have exhibited considerable potential for next-generation electroluminescent materials for lighting and display.Nevertheless,the presence of defects within these perovskites has a substantial influence on the emission efficiency and durability of the devices.In this study,we revealed a synergistic passivation mechanism on perovskite films by using a dual-functional compound of potassium bromide.The dual functional potassium bromide on the one hand can passivate the defects of halide vacancies with bromine anions and,on the other hand,can screen the charged defects at the grain boundaries with potassium cations.This approach effectively reduces the probability of carriers quenching resulting from charged defects capture and consequently enhances the radiative recombination efficiency of perovskite thin films,leading to a significant enhancement of photoluminescence quantum yield to near-unity values(95%).Meanwhile,the potassium bromide treatment promoted the growth of homogeneous and smooth film,facilitating the charge carrier injection in the devices.Consequently,the perovskite light-emitting diodes based on this strategy achieve a maximum external quantum efficiency of~21%and maximum luminance of~60,000 cd m^(-2).This work provides a deeper insight into the passivation mechanism of ionic compound additives in perovskite with the solution method. 展开更多
关键词 Synergistic passivation strategy Defects passivation Dielectric screening Perovskite light-emitting diodes
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Giant efficiency and color purity enhancement in multicolor inorganic perovskite light-emitting diodes via heating-assisted vacuum deposition 被引量:1
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作者 Boning Han Qingsong Shan +2 位作者 Fengjuan Zhang Jizhong Song Haibo Zeng 《Journal of Semiconductors》 EI CAS CSCD 2020年第5期91-98,共8页
Inorganic perovskites(Cs Pb X3(X=I,Br,Cl))have broad prospection in the field of high-definition displaying due to its excellent optoelectronic characteristics.The vacuum deposition process possesses advantages and co... Inorganic perovskites(Cs Pb X3(X=I,Br,Cl))have broad prospection in the field of high-definition displaying due to its excellent optoelectronic characteristics.The vacuum deposition process possesses advantages and competitiveness in the industrialized production.However,the performance of light emitting diodes(LEDs)based on vacuum-deposited is incredibly low.Herein,we proposed a heating-assisted vacuum deposition(HAVD)method to construct inorganic perovskite LEDs(Pe LEDs)with enhanced performance.The roughness and crystallinity of perovskite film were improved by regulating the heating treatment of substrates.And the perovskite film exhibited largely rise in luminescence,with decreasing defect density.Consequently,with the optimized temperature,the green Pe LEDs exhibited 100-fold improvement of external quantum efficiency(EQE)with the luminance of up to 11941 cd/m2,and the full width at half-maximum(FWHM)of the electroluminescence(EL)spectra was decreased from 25 to 17 nm.At the same time,the red and blue Pe LEDs also exhibited obvious enhancement in EQE and luminance by HAVD method,and both the FWHM of EL spectra dropped below 20 nm,exhibiting excellent high color purity.HAVD strategy has a huge potential to be a new commonly used method for low-cost fabrication of displays and lighting. 展开更多
关键词 all-inorganic perovskites LIGHT-EMITTING diodes HEATING ASSISTED vacuum deposition Cs Pb Br3 color purity
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