We experimentally demonstrate a wavelength-spacing tunable multiwavelength erbium-doped fiber laser based on degenerate four-wave mixing in dispersion-shifted incorporating multiple-fiber Bragg gratings. have achieved stable operation of the laser, which has 0.8 nm spacing ten-channel lasing wavelengths and high extinction ratio more than ∼45 dB, at room temperature. The output power is stable, so peak fluctuation less ∼0.2 dB. By changing properties such as loss polarization state multiple...

We present a graphic method of analyzing the spectral displacements long-period fiber grating as function ambient index. Mode dependence maximum displacement, disappearance particular resonance peak, and behavior when index is larger than that cladding material are investigated compared with experimental results.

We propose a simple and flexible multiwavelength Raman-fiber-laser-based long-distance remote-sensing scheme for simultaneous measurement of strain temperature by use fiber Bragg gratings. By combining two uniform gratings with tunable chirped grating, we readily achieve two-channel sensing probes high extinction ratio more than ?50?dB over 50-km distance. When are applied, lasing wavelength separation shift occur, respectively, since the have identical material composition different...

This study reports a synthetic polymer functionalized with catechol groups as dental adhesives. We hypothesize that catechol-functionalized functions adhesive for wet dentin surfaces, potentially eliminating the complications associated saliva contamination. prepared random copolymer containing and methoxyethyl in side chains. The mechanical properties of to surface presence water salivary components were determined. It was found new combined an Fe3+ additive improved bond strength...

We newly propose and experimentally demonstrate a differential measurement scheme for Brillouin optical correlation domain analysis, where the difference between gain spectra constructed by normal phase-modulated pump waves are analyzed to measure local frequencies in fibers. In experiments, five-fold enhancement spatial resolution is obtained compared an ordinary BOCDA system under same modulation parameters, as result of improved dynamic range suppression background noises.

We propose and experimentally demonstrate a switchable multiwavelength erbium doped fiber laser based on highly nonlinear dispersion shifted multiple Bragg gratings. A optical loop mirror is implemented in the ring cavity to stabilize output at room temperature. Multiple gratings with wavelength spacing of 0.8 nm are connected an arrayed waveguide grating establish multichannel filter. The high quality extinction ratio ~60 dB flatness ~0.5 realized. polarization rotation can provide...

We demonstrate a novel kind of tunable optical delays based on dynamic grating generated by Brillouin scattering in an fiber. An axial strain gradient is applied to 15 m section polarizationmaintaining fiber, and the reflection position-selectively controlling frequencies pump waves. Tunable time up 132 ns are achieved with 82 Gaussian pulse.

We fabricated an elliptical hollow-core photonic bandgap fiber (EC-PBGF) by controlling lateral tension in the hollow core region during drawing process. The absolute value of group modal birefringence becomes relatively high near boundaries. also experimentally measured strain and temperature sensitivities EC-PBGF-based Sagnac loop interferometer. were very much dependent upon wavelength. Moreover this PBGF-based interferometer can be a good sensor physical parameters such as temperature.

A series of laboratory and field tests were performed to evaluate the applicability an optical fiber sensor system in instrumentation piles. multiplexed system, constructed by arranging several Fiber Bragg Grating (FBG) sensors along a single line fiber, is capable measuring local axial strains as function wavelength shifts. The distributions load three model piles test pile evaluated from measured FBG are found be comparable, terms both magnitude trend, with those obtained conventional...

We demonstrate an all-fiber Tm-doped soliton laser with high power by using a monolayer graphene saturable absorber (SA). Large area, uniform was transferred to the surface of side-polished fiber (SPF) realize in-line SA that operates around 2 μm wavelength. To increase nonlinear interaction graphene, we applied over-cladding onto SPF, where enhanced optical absorption at observed. All-fiber mode-locked built including our SA, which stably delivered pulses 773 fs pulse duration. The measured...

A theoretical model to describe in-band pumped holmium doped silica fiber lasers is presented. The established based upon theory and parameters obtained from published research works. Both core-pumped system cladding-pumped are simulated with the model. simulation results agree well most experimental results, for cases in which show discrepancy disagreement can be reasonably explained. Through numerical analysis it found that besides common negative factors such as non-radiative decay, loss,...

The purpose of this study was to investigate the distribution Salmonella species in an integrated broiler supply chain Korea. A total 1,214 samples from various steps production company including breeder farms, trucks, slaughterhouse, and retail chicken meats were collected investigated. detected 195 samples. highest prevalence observed transporting trucks (71.43%), followed by slaughterhouse (63.89%) farms (16.05%). Hadar most frequently isolated serotype (83.08%). All isolates investigated...

Dental light-cured resins can undergo different degrees of polymerization when applied in vivo. When is incomplete, toxic monomers may be released into the oral cavity. The present study assessed cytotoxicity materials, using sample preparation methods that mirror clinical conditions. Composite and bonding were used divided four groups according to method: uncured; directly cured samples, which after being placed on solidified agar; post-cured samples polymerized before “removed unreacted...

We experimentally demonstrate a new approach for the demodulation of fiber Bragg grating (FBG) strain sensor by combining tilted FBG demodulator with temperature-independent property and dual head temperature-discriminating property. This technique guarantees stable measurement independent temperature perturbation at both sides without any additional temperature-isolation or temperature-referencing process has minimum resolvable 10 μstrain. The ranges operating which guarantee dynamic range...

We experimentally demonstrate a flexibly switchable multiwavelength fiber laser with multiple functionalities like wide tuning range of lasing wavelength, wavelength spacing, and the number channels simultaneously. The is controlled in from 1510 to 1620 nm based on effect nonlinear gain compression semiconductor optical amplifier incorporated an erbium-doped amplifier. spacing are readily by effective length polarization-maintaining (PMF) segments intracavity PMF Lyot-Sagnac filter.

To reduce the incidence of postsurgical bacterial infection that may cause implantation failure at implant-bone interface, surface treatment titanium implants with antibiotic materials such as silver (Ag) has been proposed. The purpose this work was to create TiO2 nanotubes using plasma electrolytic oxidation (PEO), followed by formation an antibacterial Ag nanostructure coating on nanotube layer a magnetron sputtering system. PEO performed commercially pure Ti sheets. added onto resulting...

We propose and experimentally demonstrate a Brillouin optical correlation domain analysis system adopting time-domain data processing differential measurement for simultaneous interrogation of multiple sensing points. Continuous probe pulsed pump waves are simultaneously frequency-modulated by MHz-order sinusoidal RF wave so that peaks sequentially generated according to the propagation along fiber under test (FUT). The gain spectrum each peak is obtained interrogated moving window averaging...

An interferometric strain-sensing system that combines an unbalanced Mach–Zehnder wavelength discriminator and spliced different-diameter fiber Bragg gratings is presented has the capability to distinguish strain from temperature effects. Because are written in 135- 165-µm-diameter fibers drawn same preform, when they show similar sensitivities but different responses applied strain. Thus relative difference of two affected only by strain, one can measure it accurately monitoring amplitude...

We propose a simple and flexible multiwavelength Raman fiber laser based on phase-shifted Bragg gratings (FBGs) tunable chirped FBG. Using configuration with single FBG FBG, we readily achieved simultaneous two-channel sensing probes high extinction ratio of more than 50 dB over 50-km distance. The output was stable the peak fluctuation less 0.5 dB. temperature strain sensitivities are estimated to be 10.1 pm∕°C 7.5 pm∕μstrain, respectively.

We experimentally demonstrate a flexibly tunable multiwavelength erbium-doped fiber laser based on degenerate four-wave mixing in dispersion-shifted fiber. successfully achieve the stable operation of at room temperature. The number channels and wavelength spacing proposed can be controlled by combination two polarization maintaining segments intracavity Lyot-Sagnac filter. 1.0 nm-spacing eleven channel 0.8 seventeen lasing wavelengths also controller.

A simple optical signal demodulation technique is demonstrated for multi-point interrogation of fiber Bragg grating sensors. The wavelength-division responses polarization-maintaining Sagnac loop filters are flexibly controlled to interrogate the simultaneous intensity changes from independent wavelength shifts multiple Experimental performance also show detection separated FBG sensing signals by individual photo detectors.