- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Efficient fiber in-line single photon source based on colloidal single quantum dots on an optical nanofiber
摘要： We demonstrate a fiber in-line single photon source based on a hybrid system of colloidal single quantum dots deposited on an optical nanofiber and cooled down to cryogenic temperature (3.7 K). We show that a charged state (trion) of the single quantum dot exhibits a photo-stable emission of single photons with high quantum efficiency, narrow linewidth (3 meV FWHM) and fast decay time ( 10.0 ± 0.5 ns). The single photons are efficiently coupled to the guided modes of the nanofiber and eventually to a single mode optical fiber. The brightness (efficiency) of the single photon source is estimated to be 16 ± 2% with a maximum photon count rate of 1.6 ± 0.2 MHz and a high single photon purity ( g2(0) = 0.11 ± 0.02 ). The device can be easily integrated to the fiber networks paving the way for potential applications in quantum networks.
关键词： quantum dots,single photon source,quantum networks,optical nanofiber,cryogenic temperature
更新于2025-09-19 17:13:59
-
Self‐assembled core‐shell structured organic nanofibers fabricated by single‐nozzle electrospinning for highly sensitive ammonia sensors
摘要： Electrospinning is a unique method to prepare 1-dimentional nanofiber for large-scale manufacturing. Here in, we demonstrated chemical sensors based on the semiconducting nanofibers with core-shell structure by simple single-nozzle electrospinning with the spontaneous phase separation. The core-shell structure nanofiber has large active sites which make it highly sensitive to chemical analytes. The thickness of the sensing shell can be tuned by controlling the mass ratio of core and shell components. As a demonstration, the nanofiber-based sensor exhibits high sensitivity to low-concentration ammonia (ppb level), as well as stability and reversibility. This unique fast single-nozzle electrospinning technique used to fabricate semiconducting nanofibers with core-shell structure provides a facile and designable process for the integration of multifunctional organic semiconducting layer into the organic electronic system.
关键词： nanofiber,chemical sensor,core-shell structure,electrospinning
更新于2025-09-19 17:13:59
-
Fabrication of Carbon-decorated Al<sub>2</sub>O<sub>3</sub> Composite Powders using Cellulose Nanofiber for Selective Laser Sintering
摘要： In this study, systematic investigation using cellulose nanofiber (CellNF) as a carbon source for selective laser sintering (SLS) of Al2O3 was conducted. A composite powder that consisted of CellNF and Al2O3 was fabricated using electrostatic adsorption (EA) method in aqueous suspension. Heat-treatment temperature of 500 and 800°C was compared for the conversion of CellNF to carbon residue (CR) in the Al2O3 composite. After that, the parameters involving the volume fraction of CR and effect of Al2O3 particle size in the CR-Al2O3 composite particle were also investigated in order to obtain an optimized condition of the CR-Al2O3 composite particle for SLS. From the results obtained, 1.5 wt% CR-Al2O3 with alumina size of 0.8 μm that was heat-treated at 800°C exhibited optimum laser sinter ability owing to the good CR distribution over a higher surface area that promoted good laser adsorption for the alumina sintering.
关键词： additive manufacturing,nano-assembly technique,selective laser sintering,cellulose nanofiber,electrostatic adsorption
更新于2025-09-16 10:30:52
-
Radiative properties of scattering media containing directionally controlled nanofibers
摘要： Directional control of radiation could be useful in a range of scientific and industrial applications. This study evaluated the possibility of directional control of radiation using nanofibers. Herein, scattering media containing directionally controlled nanofibers were assembled, and their relative directional radiative intensity was measured by constructing an optical system comprising a paraboloidal mirror and a charge-coupled device (CCD) camera. The influence of polarized light on relative light intensity was confirmed and compared to the theoretical result of a single nanofiber. The scattering direction of the scattered light was found to differ based on the material and size of the nanofibers. In addition, the scattering direction of the scattered light changed according to the incident angle of the irradiated light. Therefore, the results of this study suggest that radiation can be directionally controlled using a scattering medium containing nanofibers with controlled orientations.
关键词： Nanofiber,Scattering media,Optical device,Radiative property,Directional control
更新于2025-09-16 10:30:52
-
Highly enhanced Raman scattering with good reproducibility observed on a flexible PI nanofabric substrate decorated by silver nanoparticles with controlled size
摘要： Surface-enhanced Raman scattering (SERS) spectroscopy is considered as a highly powerful analytical tool for environmental contaminants monitoring, detection of bio/chemical warfare agents, explosive detection and biological sensing. In this study, silver nanoparticles (Ag NPs) decorated polyimide (PI) nanofabric was successfully prepared as an active flexible substrate for SERS. Without any surface modification and activation, this Ag@PI nanofabric SERS substrate was prepared via an integrated process of electrospinning and ion exchange-in situ reduction. ATR-FTIR, ICP, XRD, SEM, and TGA were used to investigate the influencing factors during preparation. p-Aminothiophenol (p-ATP) was used as the probe molecule to characterize the SERS performance of Ag@PI nanofabric substrate. As a result, this Ag@PI nanofabric exhibits remarkable enhancement effect (EF = 9.0 × 103), good reproducibility, ultra-low detection limit (10?14 mol/L), and a good linear relationship between the concentration of p-ATP and intensity of its characteristic peak, making it a desirable candidate as the SERS substrate.
关键词： Nanofiber,Polyimide,Substrate,SERS,Silver nanoparticle
更新于2025-09-16 10:30:52
-
Self-trapped nanoparticle binding via waveguide mode
摘要： In this paper, we study a stable optomechanical system based on a nanoparticle chain coupled to a waveguide mode. Under the plane wave excitation the nanoparticles form a stable self-organized periodic array along waveguide axis through the transverse binding effect. We show that owing to the long-range interaction between the nanoparticles the trapping potential for each nanoparticle in the chain increases linearly with the system size, making the formation of long chains more favourable. We show that for an optical nanofiber platform the binding energy for two nanoparticles is in the range of 9 ÷ 13 kT reaching the value of 110 kT when the chain size is increased to 20 nanoparticles. We also suggest the geometry of the two counter-propagating plane waves excitation, which will allow trapping the nanoparticles close to the optical nanofiber providing efficient interaction between the nanoparticles and the nanofiber.
关键词： one-dimensional interaction,nanofiber,Optical binding,self-assembly,optical force
更新于2025-09-12 10:27:22
-
Polyvinylpyrrolidone composite nanofibers as efficient substrates for surface-assisted laser desorption/ionization mass spectrometry
摘要： A matrix-free laser desorption/ionization mass spectrometry (LDI-MS) approach was developed using electrospun composite nanofibers with controllable size, morphology and composition. Composite polyvinylpyrrolidone (PVP) nanofibers with added nanoparticles to enhance the absorption of laser energy absorber were studied. Fractal dimensional analysis was conducted to evaluate the electrospinning process for the first time, which provided useful information on the repeatability of nanofiber production. The performance of the nanofiber-assisted laser desorption/ionization method was investigated through characterization of small drug molecules and synthetic oligomers. Homogeneous sample distribution was achieved by eliminating the “sweet spot”, resulting in good reproducibility. Mass spectra features clean background, that is especially beneficial for interpretation of small molecules. High sensitivity for small drug molecules and synthetic oligomers was obtained with limits of detection limits down to the low attomolar range. The combination of composite nanofibers with LDI-MS is a versatile and sensitive approach for detection and characterization of analytes with broad range of molecular weight.
关键词： Drug molecules,Surface-assisted laser desorption/ionization,Electrospinning,Synthetic polymers,polymeric nanofiber
更新于2025-09-12 10:27:22
-
Improved formaldehyde gas sensing properties of well-controlled Au nanoparticle-decorated In2O3 nanofibers integrated on low power MEMS platform
摘要： Approaches for the fabrication of a low power-operable formaldehyde (HCHO) gas sensor with high sensitivity and selectivity were performed by the utilization of an effective micro-structured platform with a micro-heater to reach high temperature with low heating power as well as by the integration of indium oxide (In2O3) nanofibers decorated with well-dispersed Au nanoparticles as a sensing material. Homogeneous In2O3 nanofibers with the large specific surface area were prepared by the electrospinning following by calcination process. Au nanoparticles with the well-controlled size as a catalyst were synthesized on the surface of In2O3 nanofibers. The Au-decorated In2O3 nanofibers were reliably integrated as sensing materials on the bridge-type micro-platform including micro-heaters and micro-electrodes. The micro-platform designed to maintain high temperature with low power consumption was fabricated by a microelectromechanical system (MEMS) technique. The micro-platform gas sensor consisting with Au-In2O3 nanofibers were fabricated effectively to detect HCHO gases with high sensitivity and selectivity. The HCHO gas sensing behaviors were schematically studied as a function of the gas concentration, the size of the adsorbed Au nanoparticles, the applied power to raise the temperature of a sensing part and the kind of target gases.
关键词： Formaldehyde,Gold nanoparticle,In2O3 nanofiber,Gas sensor,Micro-platform,Low power
更新于2025-09-12 10:27:22
-
A Kirigami Concept for Transparent and Stretchable Nanofiber Networks-based Conductors and UV Photodetectors
摘要： To meet the increasing demand for wearable electronics today, fabrication of the stretchable devices becomes crucial. In this respect, a stretchable conductor is an essential component for achieving stretchability of the device. Herein, a stretchable and transparent conductor unit, Au-metallized PVP (Au@PVP) nanofiber network on a kirigami-structured PDMS substrate, was newly developed. By a series of comparative studies, the effectiveness of our strategies to the sensing material owing to its high sensitivity for UV light and large surface to volume ratio. To point out its applicability, we fabricated a transparent and stretchable photodetector having the same geometry. ZnO nanorod, the 1D transparent metal oxide nanostructure, is used as a resistance, ~50% increase. It also exhibited ~80% transparency, as well as excellent durability. stretchable conductor showed high stretchability of 110% without significant change in invariant electrical conductivity and high stretchability is convincingly demonstrated. Our The resulting device showed outstanding ON/OFF ratio of 1020 at its original state and 440 under 80% strain. Its fast response/reset time, high transparency and stable performance indicate the feasibility of the stretchable and transparent optoelectronic device.
关键词： metal nanofiber network,transparent,photodetector,wearable electronics,kirigami,stretchable
更新于2025-09-11 14:15:04
-
Constructing hierarchical SnO2 nanofiber/nanosheets for efficient formaldehyde detection
摘要： SnO2 nanofiber/nanosheets with hierarchical nanostructures were successfully synthesized via a facile hydrothermal method by using hollow SnO2 nanofibers as the backbone. The microstructure, morphology, chemical composition, oxidation states and surface areas of SnO2 nanofibers, SnO2 nanofiber/nanosheets and SnO2 nanosheets were comparatively studied by X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET). The characterization results indicated that the hierarchical SnO2 nanofiber/nanosheets were constructed by nanosheets arrays uniform growth on the surface of nanofibers. Sensing performances of SnO2-based nanomaterials were investigated utilizing formaldehyde (HCHO) as a target gas. Compared to SnO2 nanofibers, nanosheets and the physical mixture of nanofibers and nanosheets, the gas sensor based on SnO2 nanofiber/nanosheets exhibited better response, more excellent selectivity, transient response and trace detection ability to HCHO gas. The response (Ra/Rg) of the gas sensor is 57 toward 100 ppm HCHO at 120 °C, which is about 300% and 200% higher than that of pure SnO2 nanofibers sensors and SnO2 nanosheets sensors, respectively. Furthermore, the sensor has an excellent response/recovery performance with 4.7 s and 11.6 s for detecting 100 ppm HCHO. Both the growth process and the gas sensing mechanism of SnO2 hierarchical nanostructures were discussed. Successful preparation of SnO2 nanofiber/nanosheets is attributed to uniform decoration of seeds on the nanofibers and suitable growth conditions of nanosheets. Enhanced sensing performance mainly result from the synergistic effect of nanofibers and nanosheets, hierarchical structures and larger specific surface areas. The synthetic strategy can also be applied in preparing hierarchical materials of different constituent materials.
关键词： Homogeneous materials,SnO2 nanofiber/nanosheets,Formaldehyde gas sensors,Hierarchical structure
更新于2025-09-10 09:29:36