Polarization properties of polymer-based photonic crystal fibers

Selectively filled photonic crystal fibers with polydimethylsiloxane (PDMS), a silicon-type material, have been studied. Is has been demonstrated that polarization properties of these hybrid devices and the properties of the guided light in relation with the temperature changes, finding that the state of polarization (SOP) change with the increasing temperature but remains constant for a wide spectrum of wavelengths for a determinate temperature

Numerical and Experimental Analysis of Photonic Crystal Fiber Selectively Infiltrated with Silicon Oil

In this paper we demonstrate the numerical and experimental investigation of the photonic crystal fiber selectively infiltrated with polymer material, that is a silicon oil DC-704. The results are compared with those obtained for fully infiltrated fiber. The influence of the infiltration on light propagation properties, as well as on temperature sensitivity of the fiber are also presented. The infiltration causes the formation of photonic bandgap effect, and in the case of full infiltration the bandgaps shift equal to 50 nm is observed due to the change in external temperature in the range of about 40C (i.e. from 24 to 61°C)

Hollow-Core Bragg Fiber for Bio-Sensing Applications

Theoretical analysis of propagation properties in a hollow-core Bragg fiber for bio-sensing applications has been demonstrated. Based on the Bragg fiber we propose a resonant sensor that operates on changes in refractive index of aqueous solution placed inside the hollow core. By using the transfer matrix method we analyzed the confinement loss of the $TE_{01}$ mode in the hollow-core Bragg fiber. We have shown the influence of the fiber geometry on the changes in the confinement loss. Spectral sensitivity and resolution of the sensor are also presented

Polarimetric and Bragg Optical Fiber Sensors for Stress Distribution and Temperature Measurements in Composite Materials

Composite structures are made from two or more constituent materials with significantly different physical or chemical properties and they remain separate and distinct in a macroscopic level within the finished structure. This feature allows us for introducing an optical fiber sensors matrix into the composite material. These sensors can demonstrate stress distribution inside a tested material influenced by external tensions. Two types of the optical fiber sensors, placed into one fiber simultaneously, are used as s matrix structure. One of them is based on application of the Bragg grating structure written inside the core of the fiber. Longitudinal stress modifies changes parameters of the Bragg grating and in the same, spectral characteristics of the light transmitted through the fiber. The second one is based on application of highly birefringent fibers which under external stress introduce polarization changes in the output light. These sensors placed into one fiber give a possibility to the measure two external tensions separately

Photonic Liquid Crystal Fibers with Polymers

Photonic liquid crystal fibers with polymers constitute a new solution based on liquid crystals and microstructured polymer optical fibers opening up new areas in innovative sensing and photonic devices applications. Compared with their silica-based microstructured fibers, it is easier to fabricate exotic microstructured polymer optical fibers by extrusion or drilling at low temperature; their nonlinearity is potentially stronger, the range of available polymers that may be drawn is more diverse and the biocompatibility of polymers is often better. Liquid crystals due to their attractive properties i.e., the high birefringence, high electro-optic and thermo-optic effects are a very good candidate for microstructured polymer optical fiber infiltration to obtain tunable all-in-fiber innovative photonic devices. The paper will discuss basic properties and possible applications of the polymer photonic liquid crystal fibers that will arise from their high optical tunability with external and internal factors. Current research effort is directed towards two main solutions: photonic crystal fibers and microstructured polymer optical fiber-based structures, both infiltrated with liquid crystals of tailored optical properties

Tunability and Sensing Properties of Plasmonic/1D Photonic Crystal

Gold/one-dimensional photonic crystal (Au/1D-PC) is fabricated and applied for sensitive sensing of glucose and different chemical molecules of various refractive indices. The Au layer thickness is optimized to produce surface plasmon resonance (SPR) at the right edge of the photonic band gap (PBG). As the Au deposition time increased to 60 sec, the PBG width is increased from 46 to 86 nm in correlation with the behavior of the SPR. The selectivity of the optimized Au/1D-PC sensor is tested upon the increase of the environmental refractive index of the detected molecules. The resonance wavelength and the PBG edges increased linearly and the transmitted intensity increased nonlinearly as the environment refractive index increased. The SPR splits to two modes during the detection of chloroform molecules based on the localized capacitive coupling of Au particles. Also, this structure shows high sensitivity at different glucose concentrations. The PBG and SPR are shifted to longer wavelengths, and PBG width is decreased linearly with a rate of 16.04 Å/(μg/mm(3)) as the glucose concentration increased. The proposed structure merits; operation at room temperature, compact size, and easy fabrication; suggest that the proposed structure can be efficiently used for the biomedical and chemical application