- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Review of tellurite glasses purification issues for mida??IR optical fiber applications
摘要： We reviewed the tellurite glass purification studies performed over the last 20 years, in particular dealing with the mid-infrared transmission performances. Best results are obtained under rich O2 atmosphere with platinum crucibles although Gibbs energy calculations show that other crucibles material are possible such as gold or alumina. From the point of view of the thermodynamics of involved oxidation reactions only, we identified the suitable conditions based on Gibbs energy calculations to be a synthesis temperature set above 900K and a O2 pressure around 105 Pa. The performances of the different purification technics were also compared. Finally, we analyzed the tellurite fibers recently optimized for mid-infrared which present low attenuation up to 4 μm allowing supercontinuum generation up to 5 μm.
关键词： tellurite glasses,supercontinuum generation,optical fiber,purification,mid-IR
更新于2025-09-23 15:21:01
-
An optical fiber sensor based on carboxymethyl cellulose/carbon nanotubes composite film for simultaneous measurement of relative humidity and temperature
摘要： In this paper, a carboxymethyl cellulose (CMC)/carbon nanotubes (CNTs) composite film was manufactured and used as a good humidity sensitive material to design a humidity and temperature simultaneous measurement sensor with simple structure, high sensitivity and fast response time. The sensor is constructed by a fiber Bragg grating (FBG) and then connected a hollow-core fiber (HCF) on the end face of which coated a CMC/CNTs hydrogel composite film. Through contrast experimental tests, the results show that the humidity sensitivity of the sensor with CMC film is 170.55 pm/%RH, while the sensitivity of the sensor with CMC/CNTs composite film is 230.95 pm/%RH. The humidity-insensitive FBG can be used to obtain accurate temperature information, and the temperature sensitivity is 26.35 pm/?C. This paper not only proves that CMC is an excellent humidity sensitive material for optical fiber sensors but also proves that carbon nanotubes can increase the humidity sensitivity of the hydrogel film effectively. This temperature and humidity simultaneous measurement sensor has a good application prospect.
关键词： Optical fiber sensor,Carbon nanotubes,Carboxymethyl cellulose,Humidity and temperature
更新于2025-09-23 15:21:01
-
Dependence of macro-bending loss on bending configuration of multimode optical fibers studied by ray-tracing simulation
摘要： The macro-bending loss of multimode step-index helical, s-shaped, and figure-of-eight-shaped optical fibers is investigated by ray-tracing simulation. In particular, fibers with the same radius of curvature having the three different configurations are compared. It is found that macro-bending loss strongly depends on the configuration as well as the bending curvature of the fibers. For the same curvature, the macro-bending loss of fibers in different configurations differs markedly. Thus, when comparing or reporting the macro-bending loss of multimode optical fibers, it is necessary to specify the bending radius as well as the fiber configuration.
关键词： Ray-tracing simulation,Macro-bending loss,Optical fiber
更新于2025-09-23 15:21:01
-
[IEEE 2020 Systems of Signals Generating and Processing in the Field of on Board Communications - Moscow, Russia (2020.3.19-2020.3.20)] 2020 Systems of Signals Generating and Processing in the Field of on Board Communications - Spectral Efficiency and Information Transfer Rate Over Optical Fibers in Spatial Parallelism
摘要： Spatial parallelism contribution to optical fibers spectral efficiency and to signal transfer rate is being estimated. Parallelism multiplier system parameter is introduced. Using this parameter analytical expressions are constructed to determine the optical fibers spectral efficiency and information transfer rate. Examples of spatial parallelism of optical signal transmission in few-mode and multicore fibers are given.
关键词： spatial parallelism,information transfer rate,optical fiber,spectral efficiency,parallelism multiplier
更新于2025-09-23 15:21:01
-
[IEEE 2019 Workshop on Recent Advances in Photonics (WRAP) - Guwahati, India (2019.12.13-2019.12.14)] 2019 Workshop on Recent Advances in Photonics (WRAP) - Effect of M <sup>2</sup> parameter of the fiber and the laser on the efficiency of coupling between them
摘要： We present a study on the dependence of coupling efficiency between an optical fiber and a laser on their M2 factors viz. Mf2 and M2, respectively. It is observed that the coupling efficiency is maximum for M2/ Mf2 < 1. This gives a fair idea for selection of optical fibers in coupling laser beams to optical fibers.
关键词： mode mixer,coupling efficiency,M2 factor,Optical fiber,knife edge method
更新于2025-09-23 15:21:01
-
Novel strategy for fabrication of sensing layer on thiol-functionalized fiber-optic tapers and their application as SERS probes
摘要： This work presents a new strategy to fabricate optical fiber surface-enhanced Raman scattering (SERS) probes with high-performance remote sensing prepared by thiol functionalization of silica fiber taper, and further in situ nucleation and growth of silver nanoparticles (AgNPs). The prepared fiber probes can effectively identify the analyte 4-aminothiophenol (4-ATP) with a limit of detection (LOD) as low as 2.15×10-11 M using a portable commercial Raman spectrometer. Simultaneously, such fiber probes have shown a good reproducibility with the relative standard deviation (RSD) value of 7.6%, and possessed high signal stability at room temperature over one month. Furthermore, this approach provides new insight into the fabrication of fiber SERS probe integrated the advantages in terms of sensitivity, reproducibility and stability, which shows great potential for practical SERS applications.
关键词： Thiol functionalization,SERS performance,Probe,Silver nanoparticles,Optical fiber
更新于2025-09-23 15:21:01
-
Effect of P-to-Rare Earth Atomic Ratio on Energy Transfer in Er-Yb-Doped Optical Fiber
摘要： Erbium (Er)- and Ytterbium (Yb)-doped optical fibers (EYDFs) have been used in various industrial fields as the only technology suitable for >1 W high-power amplifiers in the 1550-nm band. The output power is mainly limited by unwanted 1-μm band amplified spontaneous emissions from excited Yb3+; however, the factors affecting the output performance remain unclear. Here, we quantitatively and systematically reveal that the Phosphorus (P)-to-rare earth atomic ratio in the EYDFs has an optimal value for achieving the best output performance of EYDFs. We experimentally evaluated the quantitative relationship among co-dopants by fabricating preforms, drawing them as fibers, and measuring the amplification characteristics. At an appropriate Er concentration (0.3–0.5 wt %), a pump-to-signal conversion efficiency of 45.4% was obtained when the P/(Yb + Er) atomic ratio was around 25. This study paves the way for energy saving in high-power applications, such as high-speed optical wireless communication and long-distance optical ranging.
关键词： Phosphorus,Atomic ratio,Space communications,Energy-transfer efficiency,Amplified spontaneous emission,Erbium-Ytterbium-doped optical fiber amplifiers
更新于2025-09-23 15:21:01
-
A mm <sup>3</sup> Fiber-Coupled Scintillator for In-Core Thermal Neutron Detection in CROCUS
摘要： The article presents the development, characterization and in-core testing of a miniature neutron detector for the investigation of highly localized in-core neutronics effects in the zero-power reactor CROCUS, operated at école Polytechnique fédérale de Lausanne (EPFL), Switzerland. A ZnS:6LiF screen, mixing inorganic scintillator and neutron converter, with a surface of 1 mm2 and a thickness of 0.2 mm was coupled with a silicon photomultiplier (SiPM) via a 10-m optical fiber. Analog read-out electronics were adopted in this prototype version to process the SiPM output signal. A first campaign was carried out to assess the detection system capabilities in terms of neutron detection and counting in mixed neutron-gamma radiation fields. The miniature detector was thoroughly characterized with a Pu-Be source installed in the CARROUSEL facility, and subsequently tested inside a control rod guide tube of the CROCUS reactor in different reactor conditions, i.e. at shutdown, startup and critical. The detector shows a linear response with the reactor power increase up to 6.5 W (i.e. around 108 cm-2·s-1 total neutron flux) and excellent neutron counting capabilities when compared to other localized detection systems available in CROCUS, such as miniature fission chambers and sCVD diamond detectors. In addition, the exposure of the miniature detector to a 60Co source with an activity of ～250 GBq, combined with the computation of the gamma flux in CROCUS with the Serpent 2 Monte Carlo code, confirmed the gamma insensitivity of the system in a mixed neutron-gamma field.
关键词： miniature neutron detector,CROCUS zero-power reactor,optical fiber devices,in-core neutron detectors,miniature scintillator devices
更新于2025-09-23 15:21:01
-
Discerning Localized Thermal Heating from Mechanical Strain Using an Embedded Distributed Optical Fiber Sensor Network
摘要： Prior research has demonstrated that distributed optical fiber sensors (DOFS) based on Rayleigh scattering can be embedded in carbon fiber/epoxy composite structures to rapidly detect temperature changes approaching 1000°C, such as would be experienced during a high energy laser strike. However, composite structures often experience mechanical strains that are also detected during DOFS interrogation. Hence, the combined temperature and strain response in the composite can interfere with rapid detection and measurement of a localized thermal impulse. In this research, initial testing has demonstrated the simultaneous response of the DOFS to both temperature and strain. An embedded DOFS network was designed and used to isolate and measure a localized thermal response of a carbon fiber/epoxy composite to a low energy laser strike under cyclic bending strain. The sensor interrogation scheme uses a simple signal processing technique to enhance the thermal response, while mitigating the strain response due to bending. While our ultimate goal is rapid detection of directed energy on the surface of the composite, the technique could be generalized to structural health monitoring of temperature sensitive components or smart structures.
关键词： smart structures,distributed optical fiber sensors,temperature sensors,structural health monitoring,high energy radiation,polymer matrix composites,strain sensors,strain compensation
更新于2025-09-23 15:21:01
-
Highly sensitive and selective sensor probe using glucose oxidase/gold nanoparticles/graphene oxide functionalized tapered optical fiber structure for detection of glucose
摘要： A tapered optical fiber structure based glucose sensor using graphene oxide (GO) and gold nanoparticles (AuNPs) is presented in this study. The waist diameter and length of the taper region are 25 μm and 6 mm, respectively. The taper region was created to expose the evanescent waves to the cladding boundaries and to get interact with the external medium. Further, the cladding of tapered region is covered with GO and AuNPs to increase the biocompatibility of sensor and to initiate the phenomenon of localized surface plasmon resonance (LSPR), respectively. The synthesized GO and AuNPs show the good absorbance properties at the peak absorbance wavelengths of 230 nm and 519 nm, respectively. The characterization of synthesized nanomaterials was done by using UV–vis spectrophotometer and TEM. The characterization of nanomaterial coated fiber probe was done by using SEM and SEM-EDS. The specificity of developed sensor probe is enhanced by immobilizing them with the glucose oxidase enzyme, that oxidized only in the presence of glucose solution. The attained results show that the developed sensor model is highly sensitive for the detection of glucose concentrations in human bodies with a sensitivity of 1.06 nm/mM in the linear range of 0 mM–11 mM with the autocorrelation accuracy of 0.9386.
关键词： Localized surface plasmon resonance,Glucose oxidase,Tapered optical fiber,Gold nanoparticles,Glucose,Graphene oxide
更新于2025-09-23 15:21:01