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- 2019
- microwave photonics
- optoelectronic oscillator
- frequency division
- Optoelectronic Information Science and Engineering
- Jinan University
- Charles Darwin University
- University of Ottawa
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Narrow-Linewidth Photonic Microwave Generation Based on an Optically Injected Semiconductor Laser Subject to Subharmonic Modulation
摘要： We propose and experimentally demonstrate a scheme to acquire a narrow-linewidth photonic microwave based on an optically injected semiconductor laser (OISL) modulated by a subharmonic microwave from an (OEO). The microwave optoelectronic oscillation frequency generated by the OEO is 7.62 GHz, and the period-one (P1) oscillation frequency of the OISL is close to twice of it. Through modulating the OISL by a 1/2 subharmonic microwave generated by the OEO, the photonic microwave is locked at 15.24 GHz with a 3-dB linewidth about 1 kHz and a SSB phase noise of -94 dBc/Hz at offset frequency 10 kHz.
关键词： Optically injected semiconductor laser (OISL),Subharmonic microwave modulation,Optoelectronic oscillation (OEO)
更新于2025-09-16 10:30:52
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[IEEE 2019 International Topical Meeting on Microwave Photonics (MWP) - Ottawa, ON, Canada (2019.10.7-2019.10.10)] 2019 International Topical Meeting on Microwave Photonics (MWP) - Widely Tunable Parity-Time-Symmetric Optoelectronic Oscillator Based on a Silicon Microdisk Resonator
摘要： A widely frequency-tunable parity-time (PT)-symmetric optoelectronic oscillator (OEO) based on a silicon microdisk resonator (MDR) is proposed and experimentally demonstrated. In the proposed OEO, two mutually coupled optoelectronic loops having an identical geometry with one having a gain and the other a loss, which are equal in magnitude, light implemented by employing the reciprocity of are propagation in an MDR, to form a PT-symmetric OEO. Thanks to the PT symmetry, single-frequency oscillation with low phase noise is implemented. The tuning of the frequency is realized by thermally tuning the MDR. The proposed OEO is demonstrated experimentally. A wide frequency tunable range from 2 to 12 GHz is realized. The phase noise is measured to be -105 dBc/Hz at a 10 kHz frequency offset, which can be further reduced if the loop length is increased.
关键词： Silicon photonics,Optoelectronic oscillator (OEO),Parity-time symmetric,Microwave photonic bandpass filter,Microwave photonics,microdisk resonator
更新于2025-09-16 10:30:52
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Onlinef?hige Signalauswertung für spektraloptische Sensoren mit einer Doppelphotodiode / Online-capable signal processing for spectral-optical sensors using a double-layered photodiode
摘要： Spectral-optical sensor technology records physical as well as (bio-)chemical measurands on the basis of specific spectral property changes of the transducer. In this article a signal evaluation with a double-layered photodiode (DPD) is presented, which is a spectrally selective element and detector at the same time due to its stack structure of two different spectrally sensitive photodiode layers. Instead of extracting the spectral information from a spectrum, the centroid of the overall spectral distribution is evaluated in real time on the basis of the measured ratio of the two wavelength-dependent photocurrents. The performance of the DPD is demonstrated by means of surface temperature measurements with the phosophor NaYF4:Yb3+,Er3+. It is shown that with an integrator-based readout electronics a max. measurement deviation for the centroid wavelength of 0.1 nm can be achieved. In sum, the online-capable signal processing and compact size of the double-layered photodiode foster the on-site applicability of spectral-optical sensors for the process industry, environmental monitoring and many others fields.
关键词： thermometry,anorganic phosphors,optoelectronic interrogator,spectral-optical sensors,Double-layered photodiode
更新于2025-09-16 10:30:52
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After-Effects of Thixotropic Maneuvers on Chest Wall and Compartmental Operational Volumes of Healthy Subjects Using Optoelectronic Plethysmography
摘要： The volumes assessed by optoelectronic plethysmography (OEP) and based on a three-compartmental model provide an accurate breath-by-breath index of expiratory and inspiratory (ribcage muscles and diaphragm) muscle length. Thus, after performing thixotropic maneuvers, OEP may also provide evidence regarding the history-dependent properties of these muscles. We studied the after-effects of different thixotropic conditionings on chest wall (CW) and compartmental operational volumes of 28 healthy subjects (25.5 ± 2.2 years, FVC%pred 94.8 ± 5.5, and FEV1%pred 95.5 ± 8.9) using OEP. Conditionings were composed of inspiratory or expiratory contractions performed from total lung capacity (TLC) or residual volume (RV). The study protocol was composed of three consecutive contractions of the same maneuver, with 60 s of spontaneous breathing in between, and after-effects were studied in the first seven respiratory cycles of each contraction. Cumulative effects were also assessed by comparing the after-effects of each thixotropic maneuver. Inspiratory contractions performed from both TLC and RV acutely increased end-inspiratory (EIV) CW volumes (all p < 0.0001), mainly on both upper and lower ribcage compartments (i.e., non-diaphragmatic inspiratory muscles and diaphragm, respectively); while, expiratory contractions from RV decreased CW volumes (p < 0.0001) by reducing the upper ribcage and abdominal volumes (all p < 0.0001). The response of the thixotropic maneuvers did not present a cumulative effect. In healthy, the use of the three-compartmental model through OEP allows a detailed assessment of the diaphragm, inspiratory and expiratory muscle thixotropy. Furthermore, specific conditioning maneuvers led to thixotropy of the inspiratory ribcage, diaphragm, and expiratory muscles.
关键词： lung capacities,optoelectronic plethysmography,lung volume measurements,respiratory muscles,muscle thixotropy
更新于2025-09-16 10:30:52
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Intermolecular Interactions of Hybrid Organic Dyes Based on Coumarin 343 for Optoelectronic Applications
摘要： Understanding the intermolecular interactions in the organic dye mixtures could be critical for the design of high-performance optoelectronic devices. In the present study, we investigate the intermolecular interactions in dye systems combining two kinds of organic dyes, using the coumarin 343 (C343) as an example. The study employs the first principles calculations and the spectroscopic/electrochemical experiments to explore the intermolecular interactions (either synergistic or antagonistic) and their effects on the electronic and optical properties of the hybrid dye systems. The interactions between the coumarin dye and four other dyes, either as free dyes or as self-assembled monolayers that are adsorbed onto semiconductor substrate, are analyzed via the UV–Vis absorption, the emission and the photocurrent measurements. The four dyes include 4-(4-diethylaminophenylazo)pyridine, chlorophosphonazo III, methyl red, and catechol, which have been applied to optoelectronic devices. In particular, the interaction between C343 and 4-(4-diethylaminophenylazo)pyridine is found to be synergistic for the photocurrent generation using the aqueous electrolyte, which is not observed in other systems. The study suggests importance of the intermolecular interactions in the hybrid-dye systems, and might provide fundamental insights on the intermolecular interactions that could be leveraged to design optoelectronic devices.
关键词： synergistic,coumarin,optoelectronic,azo,TiO2 intermolecular
更新于2025-09-16 10:30:52
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Small-Molecule Donor/Polymer Acceptor Type Organic Solar Cells: Effect of Terminal Groups of Small-Molecule Donors
摘要： Small-molecule donor/polymer acceptor type (MD/PA-type) organic solar cells (OSCs) have the great advantage of superior thermal stability. However, very few small molecular donors can match polymer acceptors, leading to low power conversion ef?ciency (PCE) of MD/PA-type OSCs. In this work, we studied the effect of terminal groups of small molecular donors on the optoelectronic properties and OSC device performance of MD/PA-type OSCs. We select a benzodithiophene unit bearing carbazolyl substituents as the core, terthiophene as the bridging unit, and electron-withdrawing methyl 2-cyanoacetate, 3-ethylrhodanine, and 2H-indene-1,3-dione as the terminal groups to develop three small-molecule donors. With the increase of the electron-withdrawing capability of the terminal groups, the small molecular donors exhibit redshifted absorption spectra and downshifted LUMO levels. Among the three small-molecule donors, the one with 3-ethylrhodanine terminal group exhibits the best photovoltaic performance with the PCE of 8.0% in MD/PA-type OSCs. This work provides important guidelines for the design of small-molecule donors for MD/PA-type OSC applications.
关键词： organic solar cells,optoelectronic properties,Small-molecule donor
更新于2025-09-16 10:30:52
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Wireless Terahertz Communications
摘要： Over the past years, interest in wireless THz communications with so-called T-waves has tremendously increased [1]–[4], because the large carrier frequencies in the range 0.2 THz to 0.9 THz support wide signal bandwidths and consequently large data rates. Transmission over hundreds of meters and line rates exceeding 100 Gbit/s were demonstrated [5]–[10]. Typical atmospheric losses are 0.2 dB/100 m at 0.2 THz, 0.5 dB/100 m at 0.3 THz, 1.5 dB/100 m at 0.4 THz, and 5 dB/100 m at 0.9 THz. For transmission over a 100 m-distance, however, the unity-gain free-space propagation loss dominates. To combat this propagation loss, multiple directional antennas with a high gain per sector can be employed at the base station to boost the reach and the data throughput on transmission and reception.
关键词： T-waves,wireless THz communications,coherent reception,optoelectronic signal processing,photomixing
更新于2025-09-16 10:30:52
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Multichannel Fiber-Optic Ring Converters for Optical Sensors of Physical Quantities
摘要： We consider possible application areas for precise multichannel fiber-optic ring converters, such as optoelectronic sensors of pressure, linear displacement, vibrations and radial beats, handy medical instruments for noninvasive determination of hemoglobin and bilirubin concentration in human blood as well as determination of hyperemia and microcirculation in human soft tissues. In addition, the miniature fiber-optic ring collectors may be used when developing high-accuracy procedures and devices for measurement of light absorption and scattering coefficients of nanodispersive media and biological tissues.
关键词： bilirubin,hemoglobin,nanodispersive media,biological tissues,fiber-optic ring converter,optoelectronic sensors
更新于2025-09-16 10:30:52
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Fluorinated dithienyl-diketopyrrolopyrrole: a new building block for organic optoelectronic materials
摘要： Diketopyrrolopyrrole (DPP) derivatives have been widely used as the electron-withdrawing unit to construct donor–acceptor (D–A) conjugated systems in organic electronics. The 3,6-position flanking aromatic rings of DPP could strongly influence the optoelectronic properties of DPP-based materials. In this study, a stepwise synthesis strategy was used to prepare monofluorinated and difluorinated dithienyl-DPP. The single crystal of the difluorinated model compound was also obtained. Three polymers based on bithiophene donor and dithienyl-DPP acceptor with different fluorinated positions were synthesized. And preliminary investigations of the influence of fluorination on the optoelectronic properties were performed.
关键词： dithienyl-DPP,Diketopyrrolopyrrole,optoelectronic properties,organic electronics,fluorinated
更新于2025-09-16 10:30:52
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Graphene Photonics || Optical Properties
摘要： The linear optical properties of graphene are considered in this chapter. Optoelectronic properties are considered in Chapter 4, and nonlinear optical properties are discussed in Chapter 5. All of these properties are related to the interactions between graphene and an optical field.
关键词： optoelectronic properties,optical properties,graphene,nonlinear optical properties
更新于2025-09-16 10:30:52