- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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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) - Wavelength-Conversion Material-Mediated Semiconductor Bonding for Photovoltaic Applications
摘要： Wavelength-conversion material-mediated semiconductor wafer bonding has been demonstrated, by utilizing an adhesive and viscous organic matrix embedding fluorescent particles. The wavelength-converting heterointerface can practically lead the spectral light incidence suitable for each photovoltaic material. This bonding and interfacial scheme is expected to enhance solar cell efficiency and structure flexibility by photon management and current matching among subcells. Moreover, our novel scheme provides the bonding formation and the interfacial function generation simultaneously, and therefore potentially realizes low-cost and high-throughput production processes.
关键词： fluorescent particles,wavelength-conversion,solar cell efficiency,photovoltaic applications,semiconductor bonding
更新于2025-09-23 15:19:57
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A Quantum Cascade Laser-Based Multi-Gas Sensor for Ambient Air Monitoring
摘要： A quantum cascade laser-based sensor for ambient air monitoring is presented and five gases, affecting the air quality, can be quantified. The light sources are selected to measure CO, NO, NO2, N2O and SO2. The footprint of the measurement setup is designed to fit in two standard 19” rack (48 cm × 65 cm) with 4 height units (18 cm) whereas one is holding the optical components and the other one contains the electronics and data processing unit. The concentrations of the individual analytes are measured using 2f-Wavelength Modulation Spectroscopy (2f-WMS) and a commercially available multipass gas cell defines the optical path. In addition, CO can also be measured with a dispersion-based technique, which allows one to cover a wider concentration range than 2f-WMS. The performance of this prototype has been evaluated in the lab and detection limits in the range of 1ppbv have been achieved. Finally, the applicability of this prototype for ambient air monitoring is shown in a five-week measurement campaign in cooperation with the Municipal Department for Environmental Protection (MA 22) of Vienna, Austria.
关键词： heterodyne phase sensitive dispersion spectroscopy,ambient air,infrared,quantum cascade laser,wavelength modulation spectroscopy
更新于2025-09-23 15:19:57
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Novel gas-phase sensing scheme using fiber-coupled off-axis integrated cavity output spectroscopy (FC-OA-ICOS) and cavity-reflected wavelength modulation spectroscopy (CR-WMS)
摘要： By feeding back the reflected light from the first cavity mirror to a single-/multi-pass gas cell via a multi-mode fiber, we demonstrated a novel gas-phase analytical scheme for methane (CH4) detection by combing fiber-coupled off-axis integrated cavity output spectroscopy (FC-OA-ICOS) and cavity-reflected wavelength modulation spectroscopy (CR-WMS). This scheme has an electrical module and two optical sensing modules which are connected through both single- and multi-mode optical fibers. Long-distance gas sensing application was conducted for verifying the analytical ability of the demonstrated technique exploiting the two fiber-coupled optical modules. A detection limit of 3 parts-per-million in volume (ppmv) for an 84 s averaging time and a precision of 56 ppmv for a 150 s averaging time were achieved using FC-OA-ICOS and CR-WMS, respectively. Two different CH4 measurement ranges were achieved in the sensor system with a wide dynamic range from ~ 15 ppmv to ~ 12% for CH4 detection. Field monitoring of CH4 leakage was performed for environmental analysis under a static and mobile mode using the wireless-controlled vehicle-mounted gas sensor. The proposed gas sensing scheme with fiber-coupled dual optical modules demonstrates a good potential for long-distance field CH4 measurements, especially for those in hazardous environment where in-situ human observation is impossible.
关键词： Remote sensing analysis,Fiber-coupled,Wavelength modulation spectroscopy,Chemical gas sensor,Off-axis integrated cavity output spectroscopy
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) - Precursor reaction method with high Ga Cu(In,Ga)(S,Se) <sub/>2</sub> to achieve increased open-circuit voltage
摘要： Direct detection transceivers offer advantages, including low cost and complexity, in short- and medium-haul links. We carried out studies seeking to identify the signal formats which offer the highest information spectral densities and maximum transmission distances for direct detection links. The performance of two spectrally efficient optical signal formats, single-sideband (SSB) Nyquist pulse-shaped subcarrier modulation (SCM) and SSB orthogonal frequency-division multiplexing (OFDM), are compared by means of simulations. The comparison is performed for a range of wavelength-division multiplexing (WDM) net information spectral densities up to 2.0 b/s/Hz by varying the signal bandwidth, modulation cardinality, and WDM channel spacing. The signal formats’ tolerance to signal–signal beating interference, resulting from square-law detection, is investigated, and the Nyquist-SCM format is found to suffer lower penalties from this nonlinearity at high information spectral densities. In 7 × 28 Gb/s WDM transmission at 2.0 b/s/Hz (with electronic pre-distortion and EDFA-only amplification), Nyquist-SCM signals can be transmitted over distances of up to 720 km of standard SMF in comparison to a maximum of 320 km with the OFDM signal format.
关键词： Digital signal processing,direct detection,wavelength division multiplexing,subcarrier modulation,electronic pre-distortion,optical communication,Nyquist pulse shaping,signal–signal beating interference,orthogonal frequency division multiplexing
更新于2025-09-23 15:19:57
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Organic Printed Core-Shell Heterostructure Arrays: A Universal Approach to All-Color Laser Display Panels
摘要： We demonstrate a universal approach for realizing dual-wavelength lasing in organic core-shell structured microlaser arrays, which show great promise in serving as all-color laser display panels. By alternately printing hydrophilic and hydrophobic laser dye solutions on preprocessed substrates, we successfully obtained precisely patterned core-shell heterostructure arrays. The spatially-separated core and shell independently function as optical resonators to support dual-wavelength tunable microlasers in each heterostructure. Such a general method enables to flexibly control the lasing wavelength of the core-shell microlasers across a wide spectral range by systematically designing the gain media. Using as-prepared microlaser arrays as display panels, we achieved full-color laser displays, representing an achievable color gamut much larger than that of standard RGB space. These results may provide new insights for design concepts and device construction for novel optoelectronic applications.
关键词： laser display,organic heterostructure,core-shell structure,dual-wavelength laser,laser array
更新于2025-09-23 15:19:57
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Effects of light-emitting diodes on thermally-induced oxidative stress in the bay scallop <i>Argopecten irradians</i>
摘要： Water temperature is an important stressor that affects the physiological and biochemical responses of scallops. In this study, we investigated the effect of different light-emitting diodes (LEDs; red, green and blue) on oxidative stress in Argopecten irradians. PCR revealed MnSOD mRNA expression in the digestive diverticula, gill, adductor muscle and eye. CAT and HSP70 mRNA were expressed in the digestive diverticula, gill and adductor muscle. Additionally, we measured the changes in the expression of HSP70, MnSOD and CAT as well as H2O2 levels during thermal/laboratory stress. In the digestive diverticula, gill and adductor muscle, the mRNA expressions and activities and H2O2 levels significantly increased in response to thermal changes. The gene expressions and activities and H2O2 levels were significantly lower in scallops that received green LED light than in those that received no mitigating treatment. A comet assay revealed that thermal change groups had increased rates of nuclear DNA damage; however, treatment with green LED reduced the frequency of damage. The results indicated that low or high water temperature conditions induced oxidative stress in A. irradians but that green LED significantly reduced this stress.
关键词： short wavelength light,bivalves,Antioxidant,water temperature change
更新于2025-09-23 15:19:57
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A biased random-key genetic algorithm for routing and wavelength assignment under a sliding scheduled traffic model
摘要： The problem of routing and wavelength assignment in optical networks consists in minimizing the number of wavelengths that are needed to route a set of demands, such that demands routed using lightpaths that share common links are assigned to different wavelengths. We present a biased random-key genetic algorithm for approximately solving the problem of routing and wavelength assignment of sliding scheduled lightpath demands in optical networks. In this problem variant, each demand is characterized not only by a source and a destination, but also by a duration and a time window in which it has to be met. Computational experiments show that the numerical results obtained by the proposed heuristic improved upon those obtained by a multistart constructive heuristic. In addition, the biased random-key genetic algorithm obtained much better results than an existing algorithm for the problem, finding solutions that use roughly 50% of the number of wavelengths determined by the latter.
关键词： Routing and wavelength assignment,Sliding scheduled lightpath demands,Optical networks,Scheduled lightpath demands,Metaheuristics,Biased random-key genetic algorithm
更新于2025-09-23 15:19:57
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Dual-Wavelength Lasing in Quantum-Dot Plasmonic Lattice Lasers
摘要： Arrays of metallic particles patterned on a substrate have emerged as a promising design for on-chip plasmonic lasers. In past examples of such devices, the periodic particles provided feedback at a single resonance wavelength, and organic dye molecules were used as the gain material. Here, we introduce a flexible template-based fabrication method that allows a broader design space for Ag particle-array lasers. Instead of dye molecules, we integrate colloidal quantum dots (QDs), which offer better photostability and wavelength tunability. Our fabrication approach also allows us to easily adjust the refractive index of the substrate and the QD-film thickness. Exploiting these capabilities, we demonstrate not only single-wavelength lasing but dual-wavelength lasing via two distinct strategies. First, by using particle arrays with rectangular lattice symmetries, we obtain feedback from two orthogonal directions. The two output wavelengths from this laser can be selected individually using a linear polarizer. Second, by adjusting the QD-film thickness, we use higher-order transverse waveguide modes in the QD film to obtain dual-wavelength lasing at normal and off-normal angles from a symmetric square array. We thus show that our approach offers various design possibilities to tune the laser output.
关键词： surface lattice resonances,dual-wavelength laser,colloidal quantum dots,plasmonics,nanolaser,template stripping,polarization
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) - Experimental Methods to Replicate Power Loss of PV Modules in the Field for the Purpose of Fault Detection Algorithm Development
摘要： Phase manipulation of four-mode phase-sensitive (4MPS) process was developed as a means for suppression of high-order four wave mixing (HoFWM) terms in dual-pump driven parametric wavelength multicasting and, consequently, for reduction of inter-channel crosstalk and inter-channel interference. In contrast to the previous studies that focused on power stabilization and conversion efficiency maximization, the investigation in this paper focuses on the evolution of the inter-channel HoFWM tones, whose suppression can be accomplished by arranging the phases of signals in a complementary manner. In addition, broadband 4MPS multicasting with suppressed HoFWM effects over 100-nm bandwidth, reaching up to 12-dB suppression ratio was demonstrated.
关键词： Four-mode phase-sensitive process,wavelength multicasting,inter-channel crosstalk,parametric mixer,inter-channel interference,four wave mixing
更新于2025-09-23 15:19:57
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Evaluating the influence of laser wavelength and detection stage geometry on optical detection efficiency in a single-particle mass spectrometer
摘要： Single-particle mass spectrometry (SPMS) is a useful tool for the online study of aerosols with the ability to measure size-resolved chemical composition with a temporal resolution relevant to atmospheric processes. In SPMS, optical particle detection is used for the effective temporal alignment of an ablation laser pulse with the presence of a particle in the ion source, and it gives the option of aerodynamic sizing by measuring the offset of particle arrival times between two detection stages. The efficiency of the optical detection stage has a strong influence on the overall instrument performance. A custom detection laser system consisting of a high-powered fibre-coupled Nd:YAG solid-state laser with a collimated beam was implemented in the detection stage of a laser ablation aerosol particle time-of-flight (LAAP-TOF) single-particle mass spectrometer without major modifications to instrument geometry. The use of a collimated laser beam permitted the construction of a numerical model that predicts the effects of detection laser wavelength, output power, beam focussing characteristics, light collection angle, particle size, and refractive index on the effective detection radius (R) of the detection laser beam. We compare the model predictions with an ambient data set acquired during the Ice in Clouds Experiment – Dust (ICE-D) project. The new laser system resulted in an order-of-magnitude improvement in instrument sensitivity to spherical particles in the size range 500–800 nm compared to a focussed 405 nm laser diode system. The model demonstrates that the limit of detection in terms of particle size is determined by the scattering cross section (Csca) as predicted by Mie theory. In addition, if light is collected over a narrow collection angle, oscillations in the magnitude of Csca with respect to particle diameter result in a variation in R, resulting in large particle-size-dependent variation in detection efficiency across the particle transmission range. This detection bias is imposed on the aerodynamic size distributions measured by the instrument and accounts for some of the detection bias towards sea salt particles in the ambient data set.
关键词： LAAP-TOF,aerosol,single-particle mass spectrometry,Mie theory,laser wavelength,detection stage geometry,optical detection efficiency
更新于2025-09-23 15:19:57