- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Achieving the hypsochromic electroluminescence of ultraviolet OLED by tuning excitons relaxation
摘要： Organic light emitting diode (OLED) has huge impact on display-related fields. Due to potential applications in information storage and backlight sources for full color display, ultraviolet OLED has attracted widespread attention. In this paper, we present an inverted UV OLED device with electroluminescence (EL) peak of 369 nm. The device employs zinc oxide (ZnO) as electron injection layer (EIL), revealing a relationship between the exciton diffusion and emitting peaks. The organic-inorganic interface in the device reduces the diffusion length of excitons and that can lead to a hampered relaxation of higher energy states, resulting in a hypsochromic shift of the EL spectrum. The existence of buffer layer will affect the relaxation process. Additionally, the emission peak of the UV-OLED can be adjusted from 369 nm to 384 nm by varying kinds and thickness of the organic functional layers.
关键词： Hypsochromic shift,OLED,Exciton relaxation,Ultraviolet emission,Wavelength regulation,Diffusion model
更新于2025-09-23 15:19:57
-
Influence of wavelength on the bandwidth of W-type plastic-clad silica optical fibers
摘要： The bandwidth and steady-state loss of multimode W-type plastic-clad silica optical fibers are investigated by solving the time-dependent power flow equation. The results show how the bandwidth of W-type plastic-clad silica optical fibers can be enhanced by shifting from the red to the infrared wavelength region for different intermediate layer widths and refractive indices of the outer cladding. Such characterization of these fibers is consistent with their manifest effectiveness in reducing modal dispersion and increasing bandwidth.
关键词： steady-state loss,power flow equation,bandwidth,infrared wavelength region,W-type plastic clad silica optical fiber
更新于2025-09-23 15:19:57
-
Numerical simulation of PbSe quantum dots doped fiber ring laser with 1.7 <i>?μ</i> m wavelength
摘要： A lead selenide quantum dot-doped fiber ring laser operating at 1.7 μm wavelength is proposed and investigated by numerical simulation for the first time. Its temporal and spectral characteristics under different simulation parameters are presented. The fact that the obtained temporal profiles using different simulation parameters are largely different is observed and analyzed. These results offer us a new practical path to generate a 1.7 μm continuous-wave and pulsed laser for deep biomedical application.
关键词： fibre laser,1.7 μm wavelength,lead selenide (PbSe) quantum dot
更新于2025-09-23 15:19:57
-
Damage-free patterning of thermally sensitive CIGS thin-film solar cells: Can nanosecond pulses outperform ultrashort laser pulses?
摘要： Nanosecond pulses are usually not considered as a suitable candidate for low-damage processing of heat-sensitive materials due to high thermal effects and significant melt formation. Many studies have shown, that CIGS is thermally sensitive material and ultrashort lasers have been chosen as the primary source for the processing of CIGS cells. However, we report on the P3 scribing of CIGS thin-film solar cells with the ns pulse duration at the wavelength of 2.5 μm – a wavelength close to the mid-infrared region and compare the results with the ps pulses covering traditional wavelengths of 355 nm, 532 nm, 1064 nm, and 1342 nm. In our case, 6 ns pulses at 2.5 μm wavelength outperformed the picosecond laser sources operating at VIS and NIR wavelength range. The minimal P3 scribe conductivity of 4.7 mS/m was achieved for ns laser patterning, corresponding to simulated CIGS module efficiency loss of just 0.01%. We proposed that high absorption in the transparent conductive oxide - TCO efficiently shielded the underlying CIGS with only a fraction of energy reaching the back-contact. Finally, results show that nanosecond pulses can be as competitive as picosecond ones for P3 processing of high-efficiency CIGS devices.
关键词： CIGS,Nanosecond laser,Scribing,Picosecond laser,VIS and NIR wavelength range,Thin-film
更新于2025-09-23 15:19:57
-
[IEEE 2019 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific) - Seogwipo-si, Korea (South) (2019.5.8-2019.5.10)] 2019 IEEE Transportation Electrification Conference and Expo, Asia-Pacific (ITEC Asia-Pacific) - Optimal scheduling of critical peak pricing considering photovoltaic generation and electric vehicle load
摘要： For long-wavelength space-based radars, such as the P-band radar on the recently selected European Space Agency BIOMASS mission, system distortions (crosstalk and channel imbalance), Faraday rotation, and system noise all combine to degrade the measurements. A first-order analysis of these effects on the measurements of the polarimetric scattering matrix is used to derive differentiable expressions for the errors in the polarimetric backscattering coefficients in the presence of Faraday rotation. Both the amplitudes and phases of the distortion terms are shown to be important in determining the errors and their maximum values. Exact simulations confirm the accuracy and predictions of the first-order analysis. Under an assumed power-law relation between σhv and the biomass, the system distortions and noise are converted into biomass estimation errors, and it is shown that the magnitude of the deviation of the channel imbalance from unity must be 4–5 dB less than the crosstalk, or it will dominate the error in the biomass. For uncalibrated data and midrange values of biomass, the crosstalk must be less than ?24 dB if the maximum possible error in the biomass is to be within 20% of its true value. A less stringent condition applies if the amplitudes and phases of the distortion terms are considered random since errors near the maximum possible are very unlikely. For lower values of the biomass, the noise becomes increasingly important because the σhv signal-to-noise ratio is smaller.
关键词： Biomass,Faraday rotation,polarimetric measurements,system distortion,calibration,long-wavelength radar
更新于2025-09-23 15:19:57
-
Modal Analysis of 2-D Material-based Plasmonic Waveguides by Mixed Spectral Element Method with Equivalent Boundary Condition
摘要： For long-wavelength space-based radars, such as the P-band radar on the recently selected European Space Agency BIOMASS mission, system distortions (crosstalk and channel imbalance), Faraday rotation, and system noise all combine to degrade the measurements. A first-order analysis of these effects on the measurements of the polarimetric scattering matrix is used to derive differentiable expressions for the errors in the polarimetric backscattering coefficients in the presence of Faraday rotation. Both the amplitudes and phases of the distortion terms are shown to be important in determining the errors and their maximum values. Exact simulations confirm the accuracy and predictions of the first-order analysis. Under an assumed power-law relation between σhv and the biomass, the system distortions and noise are converted into biomass estimation errors, and it is shown that the magnitude of the deviation of the channel imbalance from unity must be 4–5 dB less than the crosstalk, or it will dominate the error in the biomass. For uncalibrated data and midrange values of biomass, the crosstalk must be less than ?24 dB if the maximum possible error in the biomass is to be within 20% of its true value. A less stringent condition applies if the amplitudes and phases of the distortion terms are considered random since errors near the maximum possible are very unlikely. For lower values of the biomass, the noise becomes increasingly important because the σhv signal-to-noise ratio is smaller.
关键词： Biomass,Faraday rotation,polarimetric measurements,system distortion,calibration,long-wavelength radar
更新于2025-09-23 15:19:57
-
High-Performance Megahertz-Frequency Resonant DC-DC Converter for Automotive LED Driver Applications
摘要： Silicon photonic interconnect (SPI) is an attractive alternative for the power-hungry and low-bandwidth metallic interconnect in multiprocessor systems-on-chip (MPSoCs). When employing SPIs for wavelength-division multiplexing (WDM)-based applications, it is essential to precisely align the central wavelengths of different photonic devices (e.g., photonic switches) to achieve a reliable communication. However, SPIs are sensitive to fabrication nonuniformity (a.k.a. fabrication process variation), which results in wavelength mismatches between devices, and hence performance degradation in SPIs. This work presents a computationally ef?cient and accurate bottom-up approach to study the impact of fabrication process variations on passive silicon photonic devices and interconnects. We ?rst model the impact of process variations at the component level (i.e., strip waveguides), then at the device level (i.e., add-drop ?lters and photonic switches), and ?nally at the system level (i.e., passive WDM-based SPIs). Numerical simulations are performed not only to evaluate the accuracy of our method, but also to demonstrate its high-computational ef?ciency. Furthermore, our study includes the design, fabrication, and analysis of several identical microresonators to demonstrate process variations in silicon photonics fabrication. The ef?ciency of our proposed method enables its application to large-scale passive SPIs in MPSoCs, where employing time-consuming numerical simulations is not feasible.
关键词： wavelength-division multiplexing,Fabrication non-uniformity,reliability,silicon photonic interconnects
更新于2025-09-23 15:19:57
-
Narrowband colloidal quantum dot photodetectors for wavelength measurement applications
摘要： High performance photodetectors based on colloidal quantum dots have been demonstrated in a wide spectral range spanning from the visible to the mid infrared. Quantum dot photodetectors typically show a low-pass type spectral response with a tunable cutoff wavelength. In this paper, we propose a method for the realization of narrowband photodetectors based on the combination of photoconductors and optical filters, both realized with colloidal PbS quantum dots. We demonstrate that an array of such narrowband photodetectors can be effectively employed for the realization of a compact wavemeter operating in the visible and near-infrared spectral range.
关键词： Narrowband photodetectors,Wavelength meter,Colloidal Quantum Dots photodetectors
更新于2025-09-23 15:19:57
-
High-power, cascaded random Raman fiber laser with near complete conversion over wide wavelength and power tuning
摘要： Cascaded Raman fiber lasers based on random distributed feedback (RDFB) are proven to be wavelength agile, enabling high powers outside rare-earth doped emission windows. In these systems, by simply adjusting the input pump power and wavelength, high-power lasers can be achieved at any wavelength within the transmission window of optical fibers. However, there are two primary limitations associated with these systems, which in turn limits further power scaling and applicability. Firstly, the degree of wavelength conversion or spectral purity (percentage of output power in the desired wavelength band) that can be achieved is limited. This is attributed to intensity noise transfer of input pump source to Raman Stokes orders, which causes incomplete power transfer reducing the spectral purity. Secondly, the output power range over which the high degree of wavelength conversion is maintained is limited. This is due to unwanted Raman conversion to the next Stokes order with increasing power. Here, we demonstrate a high-power, cascaded Raman fiber laser with near complete wavelength conversion over a wide wavelength and power range. We achieve this by culmination of two recent developments in this field. We utilize our recently proposed filtered feedback mechanism to terminate Raman conversion at arbitrary wavelengths, and we use the recently demonstrated technique (by J Dong and associates) of low-intensity noise pump sources (Fiber ASE sources) to achieve high-purity Raman conversion. Pump-limited output powers >34W and wavelength conversions >97% (highest till date) were achieved over a broad – 1.1μm to 1.5μm tuning range. In addition, high spectral purity (>90%) was maintained over a broad output power range (>15%), indicating the robustness of this laser against input power variations.
关键词： wavelength conversion,spectral purity,random distributed feedback,Raman fiber laser,high-power
更新于2025-09-23 15:19:57
-
[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Brillouin Optical Time Domain Analysis with Wavelength-locked Low-noise Pump-probe Laser Scheme
摘要： A doubly resonant short cavity Brillouin ring-laser actively stabilized with a wavelength locking system are employed as a low-RIN pump-probe source for Brillouin optical time-domain analysis (BOTDA) sensing. The developed high-stability narrow-linewidth laser scheme is compared to a long-cavity ring laser, showing the potential for enhanced temperature-strain resolutions.
关键词： wavelength-locked,temperature-strain resolutions,BOTDA,low-noise pump-probe laser,Brillouin Optical Time Domain Analysis
更新于2025-09-23 15:19:57