修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

过滤筛选

出版时间
  • 2019
研究主题
  • microwave photonics
  • optoelectronic oscillator
  • frequency division
应用领域
  • Optoelectronic Information Science and Engineering
机构单位
  • Jinan University
  • Charles Darwin University
  • University of Ottawa
202 条数据
?? 中文（中国） ▾

  • Theoretical investigation using DFT of quinoxaline derivatives for electronic and photovoltaic effects

    摘要： Photovoltaic properties of solar cells based on fifteen organic dyes have been studied in this work. B3LYP/6-311G (d,p) methods are realized to obtain geometries and optimize the electronic properties, optical and photovoltaic parameters for some quinoxaline derivatives. The results showed that time dependent DFT investigations using the CAM-B3LYP method with the polarized split-valence 6-311G (d,p) basis sets and the polarizable continuum model PCM model were sensibly able to predict the excitation energies, the spectroscopy of the compounds. HOMO and LUMO energy levels of these molecules can make a positive impact on the process of electron injection and dye regeneration. Gaps energy ΔEg, short-circuit current density Jsc, light-harvesting efficiency LHE, injection driving force ΔGinject, total reorganization energy λtotal and open-circuit photovoltage Voc enable qualitative predictions about the reactivity of these dyes.

    关键词： Computing methodology,TD-DFT,Energy,PCM,Optoelectronic,Particle physics,Quantum mechanics,Photovoltaic,Physics,Quinoxaline derivatives,Theoretical computer science,Solar cells,Molecular physics

    更新于2025-09-23 15:19:57

  • An experimental study on the blinking suppression mechanism of organic-inorganic formamidinium lead halide perovskite quantum dots on N-Type semiconductors

    摘要： Lead halide perovskite has emerged as a potential material for a wide range of applications, including solar cells, light-emitting diode displays, lasing, and single photon emitters. To optimize their utilization in optoelectronic devices, the fundamental photophysical properties, especially their charge carrier transition and blinking behaviors, must be elucidated. In this study, we investigate the blinking behaviors of single formamidinium bromide perovskite quantum dots (FAPbBr3 PQDs) on the n-type TiO2 substrate. It is suggested that the electrons from TiO2 fill the trap states of FAPbBr3 PQD during Fermi-level equilibrium, which can reduce the possibility of capturing the hot electrons from PQD into the trap states. In addition, charge separation and charge recombination processes between PQD and TiO2 are expected to shorten the duration of the OFF state, thus stabilizing the fluorescence of PQDs.

    关键词： optoelectronic devices,TiO2 substrate,charge carrier transition,perovskite quantum dots,blinking suppression

    更新于2025-09-23 15:19:57

  • Firsta??principles Investigation of the Structural, Elastic, Electronic, and Optical Properties of ?±a?? and ?2a??SrZrS3: Implications for Photovoltaic Applications

    摘要： Transition metal perovskite chalcogenides are attractive solar absorber materials for renewable energy applications. Herein, we present the first–principles screened hybrid density functional theory analyses of the structural, elastic, electronic and optical properties of the two structure modifications of strontium zirconium sulfide (needle–like α–SrZrS3 and distorted β–SrZrS3 phases). Through the analysis of the predicted electronic structures, we show that both α– and β–SrZrS3 materials are direct band gaps absorbers, with calculated band gaps of 1.38, and 1.95 eV, respectively, in close agreement with estimates from diffuse–reflectance measurements. A strong light absorption in the visible region is predicted for the α– and β–SrZrS3, as reflected in their high optical absorbance (in the order of 105 cm?1), with the β–SrZrS3 phase showing stronger absorption than the α–SrZrS3 phase. We also report the first theoretical prediction of effective masses of photo‐generated charge carriers in α– and β–SrZrS3 materials. Predicted small effective masses of holes and electrons at the valence, and conduction bands, respectively, point to high mobility (high conductivity) and low recombination rate of photo‐generated charge carriers in α– and β–SrZrS3 materials, which are necessary for efficient photovoltaic conversion.

    关键词： Solar cell,Optoelectronic properties,Density Functional Theory,chalcogenide perovskites,earth–abundant materials

    更新于2025-09-23 15:19:57

  • Zinc Oxo Clusters Improve the Optoelectronic Properties on Indium Phosphide Quantum Dots

    摘要： This study explored the effect of zinc precursors on the optical properties of InP quantum dots (QDs) by controlling the reactivity of zinc carboxylates via a simple thermal treatment. The formation of zinc oxo clusters, Zn4O(oleate)6 and Zn7O2(oleate)10, during the thermal decomposition of zinc oleate was confirmed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. By using the zinc oxo clusters as reaction precursors, high-quality InP QDs with high photoluminescence quantum yield (PLQY) and narrow full width at half maximum (FWHM) were synthesized. (Green QDs: PLQY=95%, FWHM=37 nm. Red QDs: PLQY=84%, FWHM=40 nm) The analysis results showed that the improved optoelectronic properties were achieved by two important functions of the zinc oxo clusters: 1) suppressing the rapid depletion of the highly reactive phosphorus source and inducing size uniformity of the In(Zn)P core, and 2) facilitating the formation of an oxidized buffer layer, which effectively controls defects. Likewise, the use of reactivity-controlled species is an effective strategy for the synthesis of well-designed QDs.

    关键词： full width at half maximum,InP quantum dots,optoelectronic properties,photoluminescence quantum yield,zinc oxo clusters

    更新于2025-09-23 15:19:57

  • Ag-fiber/graphene hybrid electrodes for highly flexible and transparent optoelectronic devices

    摘要： Transparent conducting electrodes (TCEs) have attracted considerable attention towards the development of flexible optoelectronic devices. In this study, mixed-dimensional TCEs are fabricated based on the two-dimensional graphene and one-dimensional electrospun metal fiber that can address the shortcomings of each electrode. In comparison with other TCEs, the Ag fiber/graphene hybrid electrodes exhibited a highly stable morphology (67% lower peak-to-valley ratio), low sheet resistance (approximately 11 Ω/sq), high transmittance (approximately 94%), high oxidation stability with excellent flexibility, and outstanding chemical stability. The multiple functionalities of the transparent and flexible hybrid structure highlight its potential for applications in emerging electronics and highly stable optoelectronics.

    关键词： transparent conducting electrodes,Ag-fiber/graphene hybrid electrodes,flexible optoelectronic devices,graphene,electrospun metal fiber

    更新于2025-09-23 15:19:57

  • A self-powered photodetector based on two-dimensional boron nanosheets

    摘要： Owing to their intriguing characteristics, the ongoing pursuit of emerging mono-elemental two-dimensional (2D) nanosheets beyond graphene is an exciting research area for next-generation applications. Herein, we demonstrate that highly crystalline 2D boron (B) nanosheets can be efficiently synthesized by employing a modified liquid phase exfoliation method. Moreover, carrier dynamics has been systematically investigated by using femtosecond time-resolved transient absorption spectroscopy, demonstrating an ultrafast recovery speed during carrier transfer. Based on these results, the optoelectronic performance of the as-synthesized 2D B nanosheets has been investigated by applying them in photoelectrochemical (PEC)-type and field effect transistor (FET)-type photodetectors. The experimental results revealed that the as-fabricated PEC device not only exhibited a favourable self-powered capability, but also a high photoresponsivity of 2.9–91.7 μA W?1 in the UV region. Besides, the FET device also exhibited a tunable photoresponsivity in the range of 174–281.3 μA W?1 under the irradiation of excited light at 405 nm. We strongly believe that the current work shall pave the path for successful utilization of 2D B nanosheets in electronic and optoelectronic devices. Moreover, the proposed method can be utilized to explore other mono-elemental 2D nanomaterials.

    关键词： two-dimensional boron nanosheets,optoelectronic devices,carrier dynamics,liquid phase exfoliation,photodetector

    更新于2025-09-23 15:19:57

  • Photodetector with Controlled Relocation of Carrier Density Peaks: Concept and Numerical Simulation

    摘要： Modern electronics faces the degradation of metal interconnection performance in integrated circuits with nanoscale feature dimensions of transistors. The application of constructively and technologically integrated optical links instead of metal wires is a promising way of the problem solution. Previously, we proposed the advanced design of an on-chip injection laser with an AIIIBV nanoheterostructure, and a functionally integrated optical modulator. To implement the efficient laser-modulator-based optical interconnections, technologically compatible photodetectors with subpicosecond response time and sufficient sensitivity are required. In this paper, we introduce the concept of a novel high-speed photodetector with controlled relocation of carrier density peaks. The device includes a traditional p-i-n photosensitive junction and an orthogonally oriented control heterostructure. The transverse electric field displaces the peaks of electron and hole densities into the regions with low carrier mobilities and lifetimes during the back edge of an optical pulse. This relocation results in the fast decline of photocurrent that does not depend on the longitudinal transport of electrons and holes. We develop a combined numerical model based on the Schrodinger-Poisson equation system to estimate the response time of the photodetector. According to the simulation results, the steep part of the photocurrent back edge has a duration of about 0.1 ps.

    关键词： combined numerical model,high-speed AIIIBV optoelectronic devices,photodetector with controlled relocation of carrier density peaks,on-chip optical interconnections,Schrodinger-Poisson equation system

    更新于2025-09-23 15:19:57

  • Nanoshell quantum dots: Quantum confinement beyond the exciton Bohr radius

    摘要： Nanoshell quantum dots (QDs) represent a novel class of colloidal semiconductor nanocrystals (NCs), which supports tunable optoelectronic properties over the extended range of particle sizes. Traditionally, the ability to control the bandgap of colloidal semiconductor NCs is limited to small-size nanostructures, where photoinduced charges are confined by Coulomb interactions. A notorious drawback of such a restricted size range concerns the fact that assemblies of smaller nanoparticles tend to exhibit a greater density of interfacial and surface defects. This presents a potential problem for device applications of semiconductor NCs where the charge transport across nanoparticle films is important, as in the case of solar cells, field-effect transistors, and photoelectrochemical devices. The morphology of nanoshell QDs addresses this issue by enabling the quantum-confinement in the shell layer, where two-dimensional excitons can exist, regardless of the total particle size. Such a geometry exhibits one of the lowest surface-to-volume ratios among existing QD architectures and, therefore, could potentially lead to improved charge-transport and multi-exciton characteristics. The expected benefits of the nanoshell architecture were recently demonstrated by a number of reports on the CdSbulk/CdSe nanoshell model system, showing an improved photoconductivity of solids and increased lifetime of multi-exciton populations. Along these lines, this perspective will summarize the recent work on CdSbulk/CdSe nanoshell colloids and discuss the possibility of employing other nanoshell semiconductor combinations in light-harvesting and lasing applications.

    关键词： Optoelectronic properties,Nanoshell quantum dots,CdSbulk/CdSe nanoshell,Colloidal semiconductor nanocrystals,Quantum confinement

    更新于2025-09-23 15:19:57

  • [IEEE IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society - Lisbon, Portugal (2019.10.14-2019.10.17)] IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society - Fast Model-Based Fault Detection in Single-Phase Photovoltaic Systems

    摘要： Besides distinct signal generation, optoelectronic oscillators (OEOs) have also been rapidly developed as emerging techniques towards sensing, measurement, and detection. In this paper, we start with the conceptual architecture and the analytical model of OEOs. Then, three operation principles behind sensing, measurement, and detection applications are categorized, including the variation on the time delay of loop, the passband reconfiguration of microwave photonic filter in loop, and the oscillation gain from injection locking, which clearly clarify the X-to-frequency mapping (X denotes target parameter or signal) for supporting practical solutions and approaches. Next, a comprehensive review to advances in OEO-based sensing, measurement, and detection applications is presented, including length change and distance measurement, refractive index estimation, load and strain sensing, temperature and acoustic sensing, optical clock recovery, and low-power RF signal detection. As a new application example, a novel approach for in-line position finding is proposed. When a long fiber Bragg grating inserted into OEO is locally heated to slightly broaden its reflection spectrum, the target position heated is mapped into the oscillating frequency shift, according to the first operation principle. A sensitivity of 254.66 kHz/cm is obtained for position finding in the experiment. Afterward, solutions for calibration and stabilization are briefly introduced, which enable us to improve the accuracy and reliability. Finally, features and future prospects on the sensing, measurement, and detection applications are discussed, such as compact and integrated OEOs.

    关键词： Optoelectronic oscillator (OEO),fiber Bragg grating,detection,measurement,oscillating frequency,sensing and sensor,position finding,photonic integrated circuits (PICs)

    更新于2025-09-23 15:19:57

  • Inorganic halide double perovskites with optoelectronic properties modulated by sublattice mixing

    摘要： All-inorganic halide double perovskites have emerged as a promising class of materials that are potentially more stable and less toxic than lead-containing hybrid organic-inorganic perovskite optoelectronic materials. In this work, 311 cesium chloride double perovskites (Cs2BB’Cl6) were selected from a set of 903 compounds as likely being stable based on a statistically learned tolerance factor (t) for perovskite stability. First-principles calculations on these 311 double perovskites were then performed to assess their stability and identify candidates with band gaps appropriate for optoelectronic applications. We predict that 261 of the 311 Cs2BB’Cl6 compounds are likely synthesizable based on a thermodynamic analysis of their decomposition to competing compounds (decomposition enthalpy < 0.05 eV/atom). Of these 261 likely synthesizable compounds, 47 contain no toxic elements and have direct or nearly direct (within 100 meV) band gaps between 1 and 3 eV as computed with hybrid density functional theory (HSE06). Within this set, we identify the triple alkali perovskites Cs2[Alk]+[TM]3+Cl6, where Alk is a group 1 alkali cation and TM is a transition metal cation, as a class of Cs2BB’Cl6 double perovskites with remarkable optical properties, including large and tunable exciton binding energies as computed by the GW-Bethe Salpeter Equation (GW-BSE) method. We attribute the unusual electronic structure of these compounds to the mixing of the Alk-Cl and TM-Cl sublattices, leading to materials with small band gaps, large exciton binding energies, and absorption spectra that are strongly influenced by the identity of the transition metal. The role of the double perovskite structure in enabling these unique properties is probed through analysis of the electronic structures and chemical bonding of these compounds as compared with other transition metal and alkali transition metal halides.

    关键词： stability,sublattice mixing,band gaps,inorganic halide double perovskites,optoelectronic properties,excitons

    更新于2025-09-23 15:19:57