Proceedings Volume 9958

Photonic Fiber and Crystal Devices: Advances in Materials and Innovations in Device Applications X

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Proceedings Volume 9958

Photonic Fiber and Crystal Devices: Advances in Materials and Innovations in Device Applications X

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Volume Details

Date Published: 21 December 2016
Contents: 6 Sessions, 35 Papers, 15 Presentations
Conference: SPIE Optical Engineering + Applications 2016
Volume Number: 9958

Table of Contents

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Table of Contents

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  • Front Matter: Volume 9958
  • Photonic Crystals, Fibers, and Thin Films: Materials and Properties I
  • Photonic Crystals, Fibers, and Thin Films: Materials and Properties II
  • Photonic Crystals, Fibers, and Thin Films: Devices and Applications I
  • Photonic Crystals, Fibers, and Thin Films: Devices and Applications II
  • Poster Session
Front Matter: Volume 9958
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Front Matter: Volume 9958
This PDF file contains the front matter associated with SPIE Proceedings Volume 9958, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.
Photonic Crystals, Fibers, and Thin Films: Materials and Properties I
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Organic-inorganic nano-composite films for photonic applications made by multi-beam multi-target pulsed laser deposition with remote control of the plume directions
Abdalla M. Darwish, Shaelynn Moore, Aziz Mohammed, et al.
There has been an explosive interest in the technique of laser assisted deposition of polymer nano-composite films exploiting the matrix assisted pulsed laser evaporation (MAPLE) with regard to the polymer host as can be judged form recent publications.1-4 In MAPLE, a frozen solution of a polymer in a relatively volatile solvent is used as a laser target. The solvent and concentration are selected so that first, the polymer of interest can dissolve to form a dilute, particulate free solution, second, the majority of the laser energy is initially absorbed by the solvent molecules and not by the solute molecules, and third, there is no photochemical reaction between the solvent and the solute. The light-material interaction in MAPLE can be described as a photothermal process. The photon energy absorbed by the solvent is converted to thermal energy that causes the polymer to be heated but the solvent to vaporize. As the surface solvent molecules are evaporated into the gas phase, polymer molecules are exposed at the gas-target matrix interface. The polymer molecules attain sufficient kinetic energy through collective collisions with the evaporating solvent molecules, to be transferred into the gas phase. By careful optimization of the MAPLE deposition conditions (laser wavelength, repetition rate, solvent type, concentration, temperature, and background gas and gas pressure), this process can occur without any significant polymer decomposition. The MAPLE process proceeds layer-by-layer, depleting the target of solvent and polymer in the same concentration as the starting matrix. When a substrate is positioned directly in the path of the plume, a coating starts to form from the evaporated polymer molecules, while the volatile solvent molecules are evacuated by the pump from the deposition chamber. In case of fabrication of polymer nanocomposites, MAPLE targets are usually prepared as nano-colloids of the additives of interest in the initial polymer solutions. Mixing the components of different nature, organic polymers and inorganic dopants, in the same target at a certain proportion and exposing them to the same laser beam not necessarily brings good quality nano-composite films. The laser pulse energy and wavelength cannot be optimized for each component individually. Also, the mixing proportion in the composite film is dictated by the initial proportion of the target and thus cannot be changed in the process. These limitations were removed in the recently proposed method of multi-beam and multi-target deposition (in its doublebeam/ dual-target variation) using a MAPLE polymer target and one inorganic target, each being concurrently exposed to laser beams of different wavelengths.5-14 Using the method, nano-composite films of polymer poly(methyl methacrylate) known as PMMA doped with a rare earth (RE) inorganic upconversion phosphor compounds were prepared. Also, a nano-composite film of thermoelectric film of inorganic aluminum-doped ZnO known as AZO was impregnated with PMMA nano-fillers with the purpose of improving electrical conductivity and thermoelectric performance.10, 14 The polymer target was a frozen (to a temperature of liquid nitrogen) PMMA solution in chlorobenzene exposed to a 1064- nm laser beam from a Q-switched Nd:YAG pulsed laser. The inorganic targets were the pellets made of the compressed micro-powders of highly efficient RE-doped NaYF4 or the sintered powder of AZO concurrently ablated with the
Quantum mechanical treatment of the third order nonlinear term in NLS equation and the supercontinuum generation
Making use of the canonical quantization theory and defining proper creation and annihilation operators, the total Hamiltonian for the pulse propagation through the optical fiber is quantized. An operator form of the nonlinear Schrodinger equation is obtained implementing the resulted Hamiltonian. We, then, use the results of the positive P-representation and obtain a coupled stochastic nonlinear Schrodinger equation. Finally, we simulate these equations and argue about supercontinuum generation process in optical fiber (especially in photonic crystal fiber).
Femtosecond laser precipitation of non-centrosymmetric crystals in glasses
C. M. Liebig, J. Goldstein, S. A. McDaniel, et al.
Optical processes that rely on second-order nonlinear optical effects such as second harmonic generation and optical parametric amplification require the use of non-centrosymmetric crystals (NCCs). Recently it has been reported that femtosecond lasers can be used to precipitate NCCs within supersaturated glasses, forming waveguide structures [1]. During laser writing, a combination of thermal gradients together with the laser polarization, cause the alignment of the polar axis of the NCC along the writing direction. Femtosecond precipitation of NCCs in glass has the potential to be a lower-cost alternative to other methods of achieving NCC waveguiding structures. In this study a widely used ferroelectric NCC, Lithium Niobate, was precipitated in 33LiO2-33Nb2O5-34SiO2 (mol%) (LNS) glass, forming crystalline aligned channels within the amorphous glassy matrix. The precipitated lithium niobate was characterized and the structural orientation determined. The waveguiding characteristics were measured for several conditions to determine optimal power and writing speed. This procedure was then modified to optimize the precipitated 1-D structures for photonic and holographic applications.
Multimode Brillouin spectrum in dual core chalcogenide photonic nanofiber for sensing applications (Withdrawal Notice)
This paper, originally published on September 7, 2016, was withdrawn from the SPIE Digital Library on October 24, 2016, at the request of the authors.
High quality tunable Brillouin optoelectronic oscillator
Mohamed Mousa, Mahmoud H. Ahmed, Kamel M. M. Hassan, et al.
An optical scheme to improve the quality of an RF signal is proposed. The 6 dB linewidth is reduced to sub hertz and the low frequency noise below 1 KHz is reduced about 10 dB. The scheme utilizes a Brillouin-semiconductor optical amplifier (SOA) ring laser fitted with an RF intensity modulator and an APD detector. The experimental results show cavity modes with FSR of 30.57 KHz due to Brillouin fiber length of 6.6 km and 6 dB bandwidth of 780 mHz typical of Brillouin lasers. The gain of the SOA balances out most of the losses in the ring mainly that due to the RF modulator. The modulated optical signal beats at the APD. The optical loop acts as a cavity filter to the RF signal. A jitter in the cavity resonances due to temperature variations is completely eliminated from the output beat signal. There is a 10 dB increase in the phase noise at the FSR frequency and its harmonics. The setup is tested with signals generated by different sources and to frequencies up to 10 GHz, the limit of the APD. Sources with RF linewidth less than the optical FSR produces one output mode with sub-hertz line width. For larger line width signals more than one RF frequency is produced, separated by the FSR, each showing the Brillouin linewidth.
Novel design of hollow-core multi clad fiber for long haul optical communication system
We have described a dispersion characteristics of hollow-core multi-clad index profiles, which include a hollow core. The designs satisfy the most important requirements for applications in long haul communication. This design fiber shows zero dispersion at 1550 nm can be obtained for the fundamental air core mode over a wide wavelength range by introducing the partial reflector layer around the core, optimizing expanded core size and silica cladding thickness. Also analyze dispersion compensating properties of these fibers. This unique structure of the fundamental air core mode is presented by the introduction of partial reflector cladding around the core. The potential applications of hollow-core multi clad fibers in long-haul optical communication system.
Photonic Crystals, Fibers, and Thin Films: Materials and Properties II
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Achieving magneto-elasto-electroporation and cell transport using core-shell magnetoelectric nanoparticles (Conference Presentation)
Soutik Betal, Moumita Dutta, Binita Shrestha, et al.
Magneto-Elasto-Electroporation (MEEP) is a magnetically controlled acoustic-electroporation observed while core-shell Magneto-electric nanoparticles interact with Biological Cells. The surface polarity change of the piezoelectric coating (BaTiO3) due to absorption of pressure created due magneto-striction of core (CoFe2O4) in AC magnetic field results in electric field (Uext) change at the external vicinity of the cell membrane when nanoparticles are nearby. This results in transmembrane Voltage (Um) change which is basically the difference in Cell’s internal potential (Uint) and external potential. The nonlinear permeability change of cell membrane due to change in Um opens the nano-pores on the membrane. The magnetic moment of the nanoparticles further helps in penetration of the Magneto-electric nanoparticles inside the cell through these magneto-electrically controlled newly opened nano-pores on cell’s membrane. MEEP is analyzed through in-vitro analysis and Mathematical equations are formulated for numerically expressing its fundamental effect. TEM imaging, XRD analysis, Zeta-potentiometer measurement and AFM imaging are confirming the coating of the piezoelectric layer on Magneto-stricitve nanoparticles, Acoustic measurements confirms the photo-acoustic and magneto-acoustic property of CoFe2O4 nanoparticles and Fluorescence microscopy as well as Confocal microscopy are confirming the penetration of particle inside the Human Epithelial cells (HEP2). Further on application of repulsive magnetic field, nanoparticles are observed to transport a group of cells in controlled boundary conditions in microfluidic chamber. Hence these nanoparticles can be used for accurate and efficient drug delivery as well as cell transport applications
Multiferroic thin film characterization probed by terahertz transient pulses (Conference Presentation)
Moumita Dutta, Xomalin G. Peralta, Amar S. Bhalla, et al.
Ultrashort THz pulses overlap with resonances through which magnetism or ferroelectricity can be probed or controlled. Low energy modes like soft mode phonons associated with the atomic displacements that result in ferroelectricity, or spin waves in magnetically ordered systems which can be either magnetic dipole active, in the case of the magnons, or electric dipole active in the case of electromagnons can be controlled using THz pulses. The interesting thing about multiferroics is that these modes can potentially be used for ultrafast magnetoelectric control. In common ferroics and multiferroics these modes often overlap well with the spectra of typical ultrashort THz pulses. In this work we exploit that unique feature of Terahertz ultrashort pulses to report on the multiferroic domain characterization of Bismuth Ferrite and Lead Iron Niobate correlating its ferroic behaviors, enhanced or reduced,with its varying doping concentration in the terahertz regime.The material properties like index of refraction and absorption coefficient thus derived using optical interferometry can be further explored for ultrafast device configuration.
An advanced regime of the anomalous acousto-optical interaction with tangential phase matching in crystalline materials
Regime of effective non-collinear acousto-optical interaction with tangential phase matching had been identified and previously observed only in two limiting cases: in tellurium dioxide (TeO2) at low acoustic frequencies (~60 MHz) and in rutile (TiO2) at ultra-high frequencies (~5 GHz). Both these limits are motivated by optical properties of the chosen materials. Low frequencies in TeO2 admit designing a wide-aperture acousto-optical cell, but limit the frequency bandwidth. While an acousto-optical cell made of TiO2 has very small aperture and exhibits low spectral resolution due to the effect of linear acoustic attenuation. Instead of those limits, we propose an advanced regime of the anomalous acousto-optical interaction with tangential phase matching, which allows us varying the frequency range and optimizing all the performances (for instance, the spectral resolution) of a wide-aperture acousto-optical cell made of the chosen crystal, as the case requires. Recently, we had suggested and successfully tested experimentally the revealed additional degree of freedom, i.e. the action of the tilt angle within the refractive indices ellipsoids to manipulate by the performances of crystalline acousto-optical cells. Now, we consider an opportunity of refining this additional degree of freedom within those ellipsoids of crystalline acousto-optical cell through some declination of the acoustic beam. For our investigations, the lithium niobate (LiNbO3) and rutile (TiO2) crystals of about 5 cm length, operating with the slow-shear acoustic mode along the acoustic axes had been selected. The needed theoretical analysis, numerical estimations, and 3D-vector diagrams have been developed to reveal potential benefits of the proposed technique.
Bistable mode of THG for femtosecond laser pulse
Vyacheslav A. Trofimov, Pavel S. Sidorov, Igor E. Kuchik
We develop an analytical solution for the THG problem with taking into account self- and cross- modulation of interacting waves. Consideration is made in the framework of long pulse duration approximation and plane wave approximation. Using the original approach, we obtain the explicit solution of Schrödinger equations describing the THG in the framework under consideration both for zero-value amplitude of a wave with triple frequency and for its non-zero value. It should be stressed that the main feature of our approach consists in conservation laws using, which correspond to wave interaction process. We found various regimes of frequency trebling and showed that the THG process possesses a bistable feature under certain condition. We found out also the THG mode, at which the intensities of interacting waves do not change along their propagation coordinate. This leads to existence of soliton solution for THG of femtosecond laser pulses.
Reconfigurable and frequency-agile on-chip microwave photonic bandpass and bandstop filters using stimulated Brillouin scattering
Amol Choudhary, Iman Aryanfar, Shayan Shahnia, et al.
In this paper, we present our recent results in the area of microwave photonics. Integrated microwave photonic bandpass and bandstop filters were realized using stimulated Brillouin scattering (SBS). Our recent breakthrough in the fabrication of chalcogenide waveguides has allowed us to achieve an on-chip SBS gain of >40 dB, enabling for the first time the tailoring of the SBS response well beyond the intrinsic linewidth (~30 MHz). An electrical comb generated by an arbitrary waveform generator was modulated onto an optical carrier to generate a broadened pump which via the SBS effect created a flat and rectangular bandpass filter response in the RF domain. Controlling the number of pump lines allowed bandwidth reconfigurability from 30 MHz to 440 MHz. The measured selectivity and the passband ripple were >20 dB and <1.9 dB, respectively and the center frequency of the filter was tuned up to 30 GHz. A bandstop filter response was realized by using a novel RF interferometry technique via accurate control of the amplitude and phase of the sidebands of the modulated probe. The bandwidth was reconfigurable from 75 MHz-300 MHz and the central frequency of the filter was tunable up to 30 GHz.
Enhanced image resolution in photonic crystal structure by modification of the surface structure
Ashwini Agarwal, Preeti Rani, Yogita Kalra, et al.
In this paper, enhanced image resolution by modification in the two dimensional (2-D) photonic crystal structures has been proposed. The equal frequency contour (EFC) analysis have been done using plane wave expansion method which shows that the structure exhibits an effective isotropic refractive index, neff = -1 at a normalized frequency of ω = 0.2908(2πc/a) for TM polarization, located near the second band. At ω = 0.2908(2πc/a) for TM polarization, the considered PhC structure behaves as a superlens, as analyzed using the finite difference time domain (FDTD) method. The image resolution and stability of the photonic crystal slab lens has been enhanced by creating disorder in the top and bottom layer of the PhC structure. The intensity field distributions of the optimized structure exhibit the enhanced image quality with full width at half maximum (FWHM) of 0.311 λ. The proposed structure can also be used to sense the different type of blood constituents.
Photonic Crystals, Fibers, and Thin Films: Devices and Applications I
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Improvements of volume holographic grating in photopolymer doped with nanorods (Conference Presentation) (Withdrawal Notice)
Liangcai Cao, Shenghan Wu, Song Zong, et al.
Publisher’s Note: This conference presentation, originally published on 2 November 2016, was withdrawn per author request.
In-line polarization holographic memory system using PQ doped PMMA photopolymer (Conference Presentation)
Shiuan-Huei Lin, Lun Kuang Lin, Vera Marinova, et al.
Polarization hologram provides some unique features over classical phase or amplitude hologram. One of the most important features is that the photo-induced anisotropy in those materials leads to the polarization-dependent diffraction from the hologram. This property is useful for many applications, such as optical interconnection, holographic data storage and bio-imaging …etc. Recently, the 9, 10-phenanthrenequinone -doped poly(methyl methacrylate) (PQ/PMMA) photopolymer with cm thickness has attracted intense research interesting for the volume holographic applications because the experiments demonstrated that PQ/PMMA photopolymers possess not only high optical quality but also negligible shrinkage effect under light exposure [3-5]. Additionally, in terms of chemical formula, the PQ/PMMA consists of planar structures PQ molecules dispersed in amorphous PMMA polymer so that it is possible to be oriented if irradiated with polarized light, resulting in a photoinduced birefringence. This phenomenon makes it capable for permanent polarization holographic recording via photochemical reaction. Thus, combining these two properties may make PQ/PMMA photopolymer attractive for volume polarization holographic applications. In this paper, we particularly characterize polarization holographic recording in our materials for high-density data storage. Then, we will demonstrate a in-line polarization holographic memory system using PQ/PMMA photopolymer.
Rigorous study of supercontinuum generation by high-order optical modes
We numerically study the supercontinuum (SC) generation in a six modes photonic crystal fiber (PCF). By solving the multimode generalised Schrdinger equation, we demonstrate the generation of SC by initially exciting the fundamental mode or one of the higher order modes and then observe the energy transfer to the other high order modes. We analyze the energy transfer between degenerate modes during propagation through the few mode PCF. A detailed investigation of the nonlinear effects on the SC process through linear and nonlinear coupling is provided which confirms the energy transfer between optical degenerate modes during propagation inside the few- mode fiber.
Mid-infrared supercontinuum generation in multimode step index chalcogenide fiber
In this paper, we propose a design of a high numerical aperture multimode hybrid step-index fiber for mid-infrared (mid- IR) supercontinuum generation (SCG) where two chalcogenide glass compositions As40Se60 and Ge10As23.4Se66.6 for the core and the cladding are selected, respectively. Aiming to get accurate modeling of the SCG by the fundamental mode, we solve the multimode generalized nonlinear Schrödinger equations and demonstrate nonlinear coupling and energy transfer between high order modes. The proposed study points out the impact of nonlinear mode coupling that should be taken into account in order to successfully predict the mid-infrared supercontinuum generation in highly nonlinear multimode fibers.
Cladding doped defect-core large mode area W-type photonic crystal fiber
Propagation characteristics of a cladding doped defect-core large mode area W-type photonic crystal fiber have been investigated by using finite element method. In the proposed structure the central air hole has been removed to form the defect core and the second layer of cladding rings around the central core have been selectively doped with different concentration of fluorine to tune the refractive index of the doped silica rods. The bend loss, dispersion, effect of bending on dispersion, and nonlinear coefficient of the proposed photonic crystal fiber design has been numerically investigated. The proposed W-type photonic crystal fiber has low bend loss, low dispersion, large-mode-area with low value of nonlinear coefficient at wavelength of 1.55μm. The structure can be utilized for telecommunication applications, for applications in high power fiber lasers, amplifiers and sensors.
Photonic Crystals, Fibers, and Thin Films: Devices and Applications II
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Cladded single crystal fibers for high power fiber lasers
W. Kim, B. Shaw, S. Bayya, et al.
We report on the recent progress in the development of cladded single crystal fibers for high power single frequency lasers. Various rare earth doped single crystal YAG fibers with diameters down to 17 μm with length > 1 m have been successfully drawn using a state-of-the-art Laser Heated Pedestal Growth system. Single and double cladding on rare earth doped YAG fibers have been developed using glasses where optical and physical properties were precisely matched to doped YAG core single crystal fiber. The double clad Yb:YAG fiber structures have dimensions analogous to large mode area (LMA) silica fiber. We also report successful fabrications of all crystalline core/clad fibers where thermal and optical properties are superior over glass cladded YAG fibers. Various fabrication methods, optical characterization and gain measurements on these cladded YAG fibers are reported.
Raman studies for stockpile reliability of missiles by detecting degradation of propellant stabilizers
Carlton Farley, Aschalew Kassu, Jonathan Mills, et al.
The objective of this study is to demonstrate a sensitive Raman technique for sensing degradation of propellant stabilizers like MNA and 2-NDPA that are commonly used in some missiles. The functionality of missiles and rockets are often evaluated by being fired or decomposed at routine time-intervals after prolonged storage. However, these destructive testing techniques for determining long-term rocket motor aging and shelf-life are extremely costly. If successful, the Raman technique could be utilized to determine the health of propellant stabilizers without dismantling the missiles as is commonly done at present. Raman technique is to measure concentrations of propellant stabilizers between 0.1-2% in glycerin. Two different lasers at 785 nm and 532 nm are used for developing this technique. A secondary objective is to develop a theoretical model that predicts temperature as a function of time and position inside the cylindrical storage container of MNA or 2-NDPA stabilizer. This model can help in understanding the thermal degradation of propellant stabilizers.
Multi-scanning mechanism enabled rapid non-mechanical multi-dimensional KTN beam deflector
In this paper, a multi-dimensional KTN beam deflector is presented. The multi-scanning mechanisms, including space-charge- controlled beam deflection, composition gradient-induced beam deflection, and temperature gradient-induced beam deflection are harnessed. Since multi-dimensional scanning can be realized in a single KTN crystal, it represents a compact and cost-effective approach to realize multi-dimensional scanning, which can be very useful for many applications, including high speed, high resolution imaging, and rapid 3D printing.
Non-uniform space charge controlled KTN beam deflector
A non-uniform space charge-controlled KTN beam deflector is presented and analyzed. We found that a non-uniform space charge can result in a non-uniform beam deflection angles. This effect can be useful for some applications such as electric field controlled beam separation. However, a non-uniform space charge needs to be avoided if one wants uniform beam deflection throughout the entire crystal.
High light extraction efficiency LEDs with asymmetric obtuse angle micro-structured roofs
This study reports a high light extraction efficiency (LEE) light emitting diode (LED) by harnessing asymmetric obtuse angle micro-structured roofs. In comparison to conventional symmetric micro-structured roofs, the LEE has been improved from 62% to 73%. This represents an 11% improvement in LEE, which is significant for LED. It is speculated that this improvement is largely due to the increased surface area and better randomization on the direction of transmitted/reflected light, which enhances the escaping probability after multiple reflections.
Design of AND logic gate using NAND gate in photonic crystal waveguides
Shiba Fatima, Preeti Rani, Yogita Kalra, et al.
In this paper, we have proposed the design of all-optical AND logic gate using the combination of universal NAND gates. The structure consists of hexagonal arrangement of air holes in silicon. The proposed structure has been designed using the finite difference time domain (FDTD) method. The optimized NAND gates have been arranged in a combination such that the combined structure behaves as an all-optical AND logic gate. The proposed structure exhibits a response period of 6.48ps and bit rate of 0.154 Tb/sec.
Poster Session
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High-birefringence photonic crystal fiber structures based on the binary morse-thue fractal sequence
Ahmed Al-Muraeb, Hoda Abdel-Aty-Zohdy
A novel index-guiding Silica glass-core hexagonal High-Birefringence Photonic Crystal Fiber (HB-PCF) is proposed, with five rings of standard cladding air circular holes arranged in four formations inspired by the Binary Morse-Thue fractal Sequence (BMTS). The form birefringence, confinement loss, chromatic dispersion, effective mode area, and effective normalized frequency are evaluated for the four PCFs operating within (1.8 - 2 μm) eye-safe wavelength range. Modeling and analysis of the four PCF formations are performed deploying full-vector analysis in Finite Element Method (FEM) using COMSOL Multiphysics. Respecting fabrication and in light of commercial availability in designing the proposed PCF structures, a high birefringence of up to (6.549 × 10-3 at 2 μm) is achieved with dispersionfree single-mode operation. Confinement loss as low as (3.2 × 10-5 - 6.5 × 10-4 dB/m for 1.8 - 2 μm range) is achieved as well. Comparison against previously reported PCF structures reveals the desirably higher birefringence of our BMTS HB-PCF. The proposed PCFs are of vital use in various optical systems (e.g.: multi-wavelength fiber ring laser systems, and tunable lasers), catering for applications such as: optical sensing, LIDAR systems, material processing, optical signal processing, and optical communication.
The influence of thermal aging on the optical coupler
Nowadays, it appears that the optical components aging faster. Therefore, it is accelerate of the research of the aging of the optical coupler by thermal stress necessary. This paper discusses finding of the influence of the thermal aging on the basic parameters of the optical coupler. The examined coupler has one input and eight outputs (1:8). The process of heat stress is carried out at 95°C in the electric drying oven where the coupler is loaded during the period of 120 hours. The optical power at the input of the coupler and the output optical powers of the individual branches of the coupler are measured after cooling to room temperature (approximately 25°C). The insertion losses of the individual branches, split ratio, total losses, homogeneity of the losses and cross-talk between individual branches are calculated using formulas. Measurements are made at wavelengths 1310 nm and 1550 nm. All optical powers are measured 20 times due to the statistical exclusion of error of measurements. The coupler is loaded during the period of 120 hours again immediately after measuring. Storing of the optical coupler in the drying oven is carried out so that is completely uniform heating of all the parts. The coupler is turn around every 30 hours. The paper contains the exact procedure of measurement of optical powers, which is followed by an evaluation of results. The results are shown for measurements before and after 5 cycles of heating.
Laser identification system based on acousto-optical barcode scanner principles
Ruslan A. Khansuvarov, Georgy I. Korol, Leonid N. Preslenev, et al.
The main purpose of the bar code in the modern world is the unique identification of the product, service, or any of their features, so personal and stationary barcode scanners so widely used. One of the important parameters of bar code scanners is their reliability, accuracy of the barcode recognition, response time and performance. Nowadays, the most popular personal barcode scanners contain a mechanical part, which extremely impairs the reliability indices. Group of SUAI engineers has proposed bar code scanner based on laser beam acoustic deflection effect in crystals [RU patent No 156009 issued 4/16/2015] Through the use of an acousto-optic deflector element in barcode scanner described by a group of engineers SUAI, it can be implemented in the manual form factor, and the stationary form factor of a barcode scanner. Being a wave electronic device, an acousto-optic element in the composition of the acousto-optic barcode scanner allows you to clearly establish a mathematical link between the encoded function of the bar code with the accepted input photodetector intensities function that allows you to speak about the great probability of a bar code clear definition. This paper provides a description of the issued patent, the description of the principles of operation based on the mathematical analysis, a description of the layout of the implemented scanner.
Fiber temperature sensor utilizing a thermomechanical MEMS detector
H. Ozan Çirkinoğlu, Habib Bilgin, Fehmi Çivitci, et al.
We propose a novel fiber sensor utilizing a thermomechanical MEMS element at the fiber tip. Owing to its Parylene/Titanium bimaterial structure, the MEMS membrane exhibits an out-of plane displacement with changing temperature. Together with the MEMS element, the embedded diffraction grating forms an in-line interferometer, from which the displacement as well as the temperature can be deduced. The fabricated detector is placed at the single-mode fiber output that is collimated via a graded index lens. This novel architecture allows for integrating MEMS detectors on standard optical fibers, and easy substitution of the MEMS detector element to alter the measurement range and the response time of the sensor.Temperature and time-constant measurements are provided and verified with reference measurements, revealing better than 20 mK temperature sensitivity and 2.5 msec response time, using low-cost laser source and photodetectors.
Detection of liquids in the near and mid-infrared based on lead-silicate suspended-core microstructured fibers
Matej Komanec, Tomas Nemecek, Dmytro Suslov, et al.
This paper reports on our recent progress with lead-silicate suspended-core microstructured optical fibers (SC- MOFs) for the detection of liquids. Simulations for SC-MOFs with one micrometer core diameter and of two different glass compositions with refractive indices of 1.67 and 1.89 at 1550 nm are discussed. Mode-field area study is performed for liquid analytes within refractive index range of 1.65-1.75. Experimental results of evanescent-wave refractometry are presented, with an impact study of uneven analyte-filling impact on the sensor performance. Studied SC-MOFs can find their application as monitoring sensors of various liquid quality especially when spectroscopic approach is pursued.
Tunable wavelength erbium doped fiber linear cavity laser based on mechanically induced long-period fiber gratings
Tunable wavelength erbium doped fiber linear cavity laser, based on mechanically induced long-period fiber gratings (MLPFG) is presented. The laser was tuned applying pressure over the MLPFG, in order to monitor this, pressure is applied over a plate with periodic grooves that has a short length, this pressure is controlled by a digital torque tester as a result tunable effect is observed. The grooves have a period of 620µm and the maximal pressure without breakpoint fiber is around 0.80lb-in2. Furthermore, the MLPFG used can be erased, reconfigured and exhibit a transmission spectra with termal stability, similar to high cost photoinduced long period gratings. In this work, by pressure increment distributed over the MLPFG from 0.40 lb-in2 to 0. 70 lb-in 2, tuned operation range of 14nm was observed and single line emission was tuned in the C telecommunication band. According to the stability analysis the signal to noise ratio was 29 dB and minimal wavelength oscillations of 0.29nm.
Generation of supercontinuum light in micro-structured fiber and polarization study at different wavelengths
F. J. Valle-Atilano, J. M. Estudillo-Ayala, J. D. Filoteo-Razo, et al.
In this work, we study the changes of polarization at different wavelengths in a supercontinuum source generated through a microchip laser in the IR spectrum. We use a microchip laser pulsed as pumped source, 1064 nm of wavelength, and a photonic crystal fiber by generated a supercontinuum spectrum. We twist the fiber to the purpose to induce birefringence and study the changes of the state of polarization, and through bandpass filters we observe a single wavelength of the broad spectrum obtained. Besides, ellipticity study for different filters and its relation with the supercontinuum results is discussed.
Multi-wavelength sensitive holographic polymer dispersed liquid crystal grating applied within image splitter for autostereoscopic display
Jihong Zheng, Kangni Wang, Hui Gao, et al.
Multi-wavelength sensitive holographic polymer dispersed liquid crystal (H-PDLC) grating and its application within image splitter for autostereoscopic display are reported in this paper. Two initiator systems consisting of photoinitiator, Methylene Blue and coinitiator, p-toluenesulfonic acid as well as photoinitiator, Rose Bengal and coinitiator, Nphenylglycine are employed. We demonstrate that Bragg gratings can be formed in this syrup polymerized under three lasers simultaneously including 632.8nm from He-Ne laser, 532nm from Verdi solid state laser, and 441.6nm from He- Cd laser. The diffraction efficiency of three kinds of gratings with different exposure wavelength are 57%, 75% and 33%, respectively. The threshold driving voltages of those gratings are 2.8, 3.05, and 2.85 V/μm, respectively. We also present the results for the feasibility of this proposed H-PDLC grating applied into image splitter without color dispersion for autostereoscopic display according to experimental splitting effect.
Phase unwrapping using binary-encoded fringe pattern for phase-shifting projected fringe profilometry
A phase unwrapping method by spatially encoding the fringe patterns is presented for phase-shifting projected fringe profilometry. For spatially isolated objects or surfaces with large depth discontinuities, unwrapping can be identified without ambiguity. Even though the surface color or reflectivity varies rapidly with position, it distinguishes the fringe order accurately.
A 3D translation stage calibrated with Michelson interferometers
Hui-Hung Lin, Kuo-Kai Hung, Lu-Yu Wang, et al.
A 3D translation stage which meets the requirement of the next-generation lithography is proposed. The Michelson interferometer is used to evaluate the moving distance for this 3-dimensional translation stage. With the help of Michelson interferometer, accuracy in the order of nanometers is desirable.
Scanning fringe projection for 3D shape measurements
A scanning fringe projection technique is presented to retrieve the 3D shape of an object with large depth discontinuities. Shadowing caused by tilted fringe projection can be eliminated. With a reliable image processing algorithm, noises and errors for surfaces on the edge area are efficiently detected and reduced.
Fabrication of holographic materials by photo-induced polymers
Shiao-Wei Kuo, Sheng-Kai Juang, Hao-Yu Tsai, et al.
A fabrication approach using PMMA [poly(methyl methacrylate)] and EGPEA (ethylene glycol phenyl ether acrylate) for holographic materials is presented. Diffraction efficiencies with various interference angles are studied. A 3D image reconstructed by this hologram is presented as well.
Electric field biased Faraday Effect in Cr-doped BiFeO3 thin film
Brandon D. Young, Ruyan Guo, Amar S. Bhalla
Multiferroics, materials which possess multiple ferroic orders, have seen a revival of interest in recent years as the need for multifunctional and multitunable devices has increased. These particular materials are of interest due to the potential to control and tune devices by both electric and magnetic fields. Examining how an external electric field alters the magneto-optic response of the well-known multiferroic, BiFeO3 (BFO), could provide useful insight into how these multiferroics would function in optical devices. The Faraday rotation of a 10% Cr-doped BFO (111) thin film on an MgO substrate was measured for three conditions using an ac magnetic field technique: no biasing electric field, a positive 2 kV/m electric field, and a negative 2 kV/m electric field. The Verdet constant for these three conditions at an optical wavelength of 632.8 nm was 20.48 ± 1.96 °/kOe-cm, 21.25 ± 3.33 °/kOe-cm, and 2.01 ± 0.5 °/kOe-cm respectively. These results demonstrate the possibility to manipulate the magneto-optic response of the thin film with an external dc electric field. Future work to both overcome the deficiencies exhibited by BFO and investigate how precisely the magneto-optic response can be controlled by an external field is presented and discussed.
High precision optical measurement of displacement and simultaneous determinations of piezoelectric coefficients
Bryan M. Gamboa, Madhuri Malladi, Ramya Vadlamani, et al.
PZT are also well known for their applications in Micro Electrical Mechanical Systems (MEMS). It is necessary to study the piezoelectric coefficients of the materials accurately in order to design a sensor as an example, which defines their strain dependent applications. Systematic study of the electro mechanic displacement measurement was conducted and compared using a white light fiber optic sensor, a heterodyne laser Doppler vibrometer, and a homodyne laser interferometry setup. Frequency dependent measurement is conducted to evaluate displacement values well below and near the piezoelectric resonances. UHF-120 ultra-high frequency Vibrometer is used to measure the longitudinal piezoelectric displacement or x33 and the MTI 2000 FotonicTM Sensor is used to measure the transverse piezoelectric displacement or x11 over 100Hz to 2MHz. A Multiphysics Finite Element Analysis method, COMSOL, is also adopted in the study to generate a three dimensional electromechanical coupled model based on experimentally determined strains x33 and x11 as a function of frequency of the electric field applied. The full family of piezoelectric coefficients of the poled electronic ceramic PZT, d33, d31, and d15, can be then derived, upon satisfactory simulation of the COMSOL. This is achieved without the usual need of preparation of piezoelectric resonators of fundamental longitudinal, transversal, and shear modes respectively.