- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 8th International Conference on Renewable Energy Research and Applications (ICRERA) - Brasov, Romania (2019.11.3-2019.11.6)] 2019 8th International Conference on Renewable Energy Research and Applications (ICRERA) - Impacts of Wind Speed and Humidity on the Performance of Photovoltaic Module
摘要： A method to precisely determine the quantum efficiency and primary photocurrent in avalanche photodiodes (APDs) is presented based on a linear relationship between excess noise factor F and gain, M. The new method is used to accurately compare performance of modern APD designs when nonlocal impact ionization effects govern the relationship between noise and gain.
关键词： Avalanche photodiode (APD),excess noise factor,near-infrared detection,impact ionization
更新于2025-09-23 15:19:57
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Acoustic Vibrations of Al Nanocrystals: Size, Shape, and Crystallinity Revealed by Single-Particle Transient Extinction Spectroscopy
摘要： Acoustic vibrations in plasmonic nanoparticles, monitored by an all-optical means, have attracted significant increasing interest because they provide unique insight into the mechanical properties of these metallic nanostructures. Al nanostructures are a recently emerging alternative to noble metal nanoparticles, because their broad wavelength tunability and high natural abundance make them ideal for many potential applications. Here we investigate the acoustic vibrations of individual Al nanocrystals using a combination of electron microscopy and single-particle transient extinction spectroscopy, made possible with a low-pulse energy, high sensitivity, and probe-wavelength-tunable, single-particle transient extinction microscope. For chemically synthesized, faceted Al nanocrystals, the observed vibration frequency scales with the inverse particle diameter. In contrast, triangularly-shaped Al nanocrystals support two distinct frequencies, corresponding to their in- and out-of-plane breathing modes. Unlike ensemble measurements, which measure average properties, measuring the damping time of the acoustic vibrations for individual particles enables us to investigate variations of the quality factor on the particle-to-particle level. Surprisingly, we find a large variation in quality factors even for nanocrystals of similar size and shape. This observed heterogeneity appears to result from substantially varying degrees of nanoparticle crystallinity even for chemically synthesized nanocrystals.
关键词： quality factor,Al nanocrystals,single-particle transient extinction spectroscopy,acoustic vibrations,nanoparticle crystallinity
更新于2025-09-23 15:19:57
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Dynamics and spectral characteristics of quantum dot semiconductor lasers under optical injection locking
摘要： The operation of an injection-locked quantum dot laser including the output characteristics, modulation response, and linewidth enhancement factor (LEF) has been investigated in detail considering the effect of homogeneous and inhomogeneous broadenings. Results demonstrate that a single-mode operation is guaranteed for a broad range of homogeneous broadening values (operation temperatures). Injection power-dependant reduction in the threshold current and a large increase in the slope efficiency and the output power have been achieved. Also, a near-zero and uniform LEF is obtained for the whole lasing spectra where drastic reduction from ~60 to 0.76 is observed for non-injected modes. The device exhibits a reduced settling time and modified modulation response especially a reduced frequency overshoot and enhanced 3dB modulation bandwidth. Obtained characteristics provide a design degree of freedom for spectral shaping and single/multi-mode operation which are favorable features for optical signal processing applications.
关键词： Optical injection locking,linewidth enhancement factor,modulation response
更新于2025-09-23 15:19:57
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Temperature-dependent photoluminescence of cesium lead halide perovskite (CsPbX <sub/>3</sub> , X = Br, Cl, I) quantum dots
摘要： Inorganic halide perovskites (CsPbX3, X = Br, Cl, I) have recently been recognized owing to having good luminescent properties. In this work, the emission peak of these perovskites has been tuned in the region of 451–636 nm by varying the halide ion composition. Temperature-dependent photoluminescence (PL) spectroscopy was used to verify the thermal quenching of PL , blue shifting of band gaps and linewidth of broadening for the CsPbX3 (X = Br, Cl, I) QD films. On the basis of fitting data, the activation energy (ΔE) and Huang–Rhys factor (S) of the CsPbX3 (X = Br, Cl, I) QD films was obtained. On moving from X = I to Br to Cl, the decrease in ΔE indicates that the excited electrons easily returned to the groundstate without the emission of radiation, ΔE decreases as S increases, the increase in the Huang–Rhys factor is indicative of enhanced electron–phonon coupling.
关键词： Huang–Rhys factor,activation energy,CsPbX3,temperature-dependent PL
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Radiation Effects in Thinned GaAs Photovoltaics Incorporating DBRs for Improved Radiation Tolerance of Multijunctions
摘要： Blind interference alignment (BIA) can greatly improve the degree of freedom with the infinite signal-to-noise ratio (SNR) assumption. Under the finite SNR condition, noise accumulation can have a significantly negative impact on SNR, inducing severe performance deterioration. In particular, in multi-cell networks, the transmitter to which a user connects can further affect its received SNR and the BIA design. To address such problem, we present a user grouping scheme for reducing noise accumulation in a single cell and analyze the impact of transmitter connections on the user grouping scheme. SNR BIA in a multi-cell network is further proposed, which jointly optimizes the transmitter connection and the user grouping scheme. Extensive simulations demonstrate that the achievable sum rate of SNR BIA is 1.36 times, 1.66 times, and 2.68 times that of data shared BIA, standard BIA, and extended BIA reported in the literature, respectively, and SNR BIA is more robust to user mobility.
关键词： SNR reduced factor,effective degree of freedom,Blind interference alignment,transmitter connection
更新于2025-09-23 15:19:57
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Investigation and Analysis of Data Rate for Free Space Optical Communications System Under Dust Conditions
摘要： In this study, the performance of free-space optics (FSO) communication link under dust conditions was analysed. The data were modulated by the non-return-to-zero technique. The optical link was investigated with varying data rates under the effect of dust conditions. The performance of the FSO system was tested in terms of the bit error rate (BER), Q-factor and received power at the maximum link. Simulation results were obtained to compare between two transmit data rates (0.3 and 0.7 Gbps). The system has a high BER at a high data rate. In the meantime, it has a high Q-factor at a low data rate.
关键词： OptiSystem 7.0,Atmospheric transmittance,FSO,BER,Dust concentration,Attenuation,Q-factor,Propagation,WDM
更新于2025-09-23 15:19:57
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[IEEE 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Xiamen, China (2019.12.17-2019.12.20)] 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall) - Design of Tunable Substrate Integrated Waveguide Cavity Resonator under Slow-wave and Fast-wave Loading Conditions
摘要： This paper provides an overview of the main features of several bibliometric indicators which were proposed in the last few decades. Their pros and cons are highlighted and compared with the features of the well-known impact factor (IF) to show how alternative metrics are speci?cally designed to address the ?aws that the IF was shown to have, especially in the last few years. We also report the results of recent studies in the bibliometric literature showing how the scienti?c impact of journals as evaluated by bibliometrics is a very complicated matter and it is completely unrealistic to try to capture it by any single indicator, such as the IF or any other. As such, we conclude that the adoption of more metrics, with complementary features, to assess journal quality would be very bene?cial as it would both offer a more comprehensive and balanced view of each journal in the space of scholarly publications, as well as eliminate the pressure on individuals and their incentive to do metric manipulation which is an unintended result of the current (mis)use of the IF as the gold standard for publication quality.
关键词： Bibliometrics,journal ranking,prestige indicators,research evaluation,impact factor,popularity indicators,Eigenfactor
更新于2025-09-23 15:19:57
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Evaluation of Chirped Fiber Bragg Grating with APD on Designed Optical Fiber Communication Link
摘要： Application of fiber Bragg grating (FBG) in optical communication is an evolving field. In this research paper, various types of chirped FBG’s (CFBG) have been used with avalanche photodiode (APD) on the designed optical fiber communication (OFC) link. Data rate of 20 Gbps and return-to-zero modulation format has been kept as fixed parameters. The designed link has been evaluated for varying fiber lengths (100, 200, 300, 400 and 500 km), various type of CFBG’s (linear, quadratic, square root and cubic root) with Gaussian apodization function, varying grating lengths (10, 20, 30, 40 and 50 mm) and operating temperatures (5°C, 10°C, 15°C, 20°C, 25°C, 30°C). The designed OFC link has also been evaluated for APD with and without CFBG. The performance evaluation matrix parameters selected are Q-factor, bit error rate and eye diagram. The OFC link employing CFBG with APD has been found to be superior. In compensating chromatic dispersion, optimum results have been observed for linear CFBG with Gaussian apodization function in comparison to other types of CFBG with 50 mm grating length for the maximum transmission distance.
关键词： bit error rate (BER),Optical fiber communication (OFC),eye diagram,chirped fiber Bragg grating (CFBG),vertical cavity surface emitting laser (VCSEL),avalanche photodiode (APD),Q-factor
更新于2025-09-23 15:19:57
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Bench marking of grid tied solar roof top photovoltaic system: a case comparison
摘要： Indian power sector having the target of 175GW of power from renewable energy, out of that 40 GW from Rooftop solar Photovoltaic system by 2022. The installed capacity of solar photovoltaic until 2017 is about 14.77 GW only. Even though in depth study has been carried out on the performance analysis, there is no bench marking has been arrived for the Indian Roof Top Solar PV system. Hence this paper has made an attempt by calculating the various parameters like performance ratio, plant capacity utilization ratio for the two 20KWp grid connected rooftop power plant in Telangana state. In addition to the above, it needs to do in depth analysis of power quality issues on roof top grid tied system.
关键词： Solar Photovoltaic Rooftop,Grid Connected,Performance Ratio,Capacity Utilization Factor
更新于2025-09-23 15:19:57
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Influence of the Subcell Properties on the Fill Factor of Two-Terminal Perovskitea??Silicon Tandem Solar Cells
摘要： The performance of a tandem solar cell depends on the performance of its constituting subcells. Although this dependency is theoretically straightforward for open-circuit voltage (Voc) and short-circuit current, it is indirect for fill factor (FF) and thus for efficiency. We study here with simple simulations the effect on the tandem performance of each subcell FF by varying systematically their series resistance, parallel resistance, and local defect. We demonstrate that series resistance impacts strongly FF for single-junction devices but marginally for tandem devices, the opposite holding for parallel resistances (shunting). We show that localized defects will be most stringent to the tandem device when they occur in the current-limiting subcell. There is thus no obvious correlation between FFs of a tandem device and of its subcells. Finally, we compare two bottom-cell designs and highlight the importance of using a high-Voc bottom cell to reach high tandem efficiencies.
关键词： series resistance,tandem solar cells,parallel resistance,perovskite-silicon,local defects,fill factor
更新于2025-09-23 15:19:57