This PDF file contains the front matter associated with SPIE Proceedings Volume 9586 including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

Large class of new photonic devices, including light emitters, chemical sensors, and energy harvesters, can be made of the polymer-inorganic nanocomposite thin films produced by the new multiple-beam pulsed laser deposition process (MB-PLD). We describe the PLD system and the film deposition process itself, particularly the multiple-beam matrix assisted pulsed laser evaporation (MB-MAPLE) version with laser beam scanning and plume direction control. We also report on the results of the investigation of optical and performance characteristics of three types of the fabricated nanocomposite thin film devices: upconversion light emitters, chemical (ammonia) sensors, and thermoelectric energy harvesters. The emitters were made of poly(methyl methacrylate) (PMMA) film impregnated with the nanoparticles of rare-earth (RE) fluorides such as NaYF₄: Yb³⁺, Er³⁺ and NaYF₄: Yb³⁺, Ho³⁺. They demonstrated bright upconversion emission in visible region being pumped with a 980-nm infra-red laser. The same films, but doped with an indicator dye, were tested as ammonia sensors. They demonstrated the drop of upconversion emission (registered by a photodetector) due to the rise of the optical absorption of the indicator dye affected by ammonia. The capability of detecting fractions of one percent (molar) of ammonia was established. The thermoelectric energy harvesters were made of nanocomposite films of aluminum-doped zinc oxide (AZO) impregnated with polymer nanoparticles. The role of the nanoparticles was to reduce the thermoconductivity and increase electroconductivity thus contributing to the improvement of the thermoelectric figure-of-merit ZT.

Huge number of new photonic devices, including light emitters, chemical sensors, and energy harvesters, etc. can be made of the nanocomposite coatings produced by the new multi-beam pulsed laser deposition (MB-PLD) process. We provide a short review of the conventional single-beam PLD method and explain why it is poorly suitable for making nanocomposite coatings. Then we describe the new MB-PLD process and system, particularly the multiple-beam matrix assisted pulsed laser evaporation (MB-MAPLE) version with laser beam scanning and plume direction control. The latter one is particularly designed to make organic (polymer) - inorganic functionalized nanocomposite coatings. Polymer film serves as a host for inorganic nanoparticles that add a specific functionality to the film. We analyze the properties of such coatings using the examples of poly(methyl methacrylate) (PMMA) films impregnated with the nanoparticles of rare-earth (RE) upconversion phosphors. They demonstrated the preservation of microcrystalline structure and bright upconversion emission in visible region of the phosphor nanoparticles after they were transferred in the polymer matrix during the MB-MAPLE process. The proposed technology has thus proven to serve its purpose: to make functionalized polymer nanocomposite coatings for a various potential applications.

A study of Terahertz response of single crystal LiNbO₃ thin films subjected to different structural and experimental configuration has been conducted in this work. In this work z-cut and x-cut ion-sliced Lithium Niobate thin films with and without embedded electrodes have been studied employing both Transmission and Reflection mode of Terahertz Spectroscopy along with z-cut single crystal in bulk form. The measurements have been performed in room temperature to probe distinctive THz-material interactions in the frequency range of 0.1-3 THz (3.34cm^-1 - 100cm^-1). The information thus obtained from the experimental investigation has been used to deduce a conclusive study on the influence of different polar domains on electrical and optical properties in THz frequency regime. Single Lorentzian oscillator model has also been used to define the THz signature thus acquired.

We report an experimental study, where Cobalt Ferrite (CoFe₂O₄) nanoparticles exhibit Photoacoustic (PA) emission peak intensity of 235.2V/J when analyzed under the Opto-Acoustic measurement setup. PA emission peak intensity decreases to 210V/J when AC Magnetic field is applied and further when Barium Titanate coated cobalt ferrite nanoparticles were analyzed, the PA peak further reduces to 68.76667V/J and with application of AC magnetic field the peak completely disappears. The measurement depicts the Photoacoustic and magnetoelastic behavior of cobalt ferrite nanoparticles.

A simple and low-cost fiber optic refractometer has been designed and demonstrated. The sensor is configured by etching a short region of a standard single-mode circularly bent fiber. Circularly bent three fiber loops are etched in equal lengths and arranged parallel to each other. The working principle of the sensor is by detecting the evanescent field modulation with respect to the change in ambient refractive index. In the present study glycerin solution with various concentrations, possessing different refractive indices is chosen as the ambient.

Bent and etched optical fiber sensors have increased sensing capabilities but they are very much prone to fracture and breakage. The proposed sensor is stable showing very less tendency towards any breakage or fracture. The sensitivity of the sensor is tested for glycerin with different concentrations. It is evident from the experimental results that with the increase of glycerin concentration the output intensity of the sensor is decreased linearly. The proposed sensor may find applications in detecting various chemical species and biochemical applications.

We have investigated ultrashort parabolic pulse formation via passive nonlinear reshaping in normal dispersive optical fibers at 1550 nm. It was investigated parabolic pulse formation in the transient-state regime and in the steady-state regime. Numerical simulations have been made based on generalized nonlinear Schrödinger equation taking into account high-order dispersion terms and high order nonlinear terms. It was examined the applicability of different commercially available fibers for parabolic pulse formation at 1550 nm. It was found that small amount of positive second-order dispersion and quite sufficient third-order dispersion can restrict strongly the formation of parabolic pulses at 1550 nm. The most suitable fiber for pulse reshaping has been found.

We numerically demonstrate the supercontinuum (SC) generation in a novel chalcogenide As₂S₅ nanowire embeddedcore into Tellurite photonic crystal fiber (PCF). This hybrid As₂S₅-tellurite small core PCF has a pitch of 0.7 μm and air hole diameter of 0.2 μm. It exhibits a zero dispersion wavelength (ZDW) of 3.25 μm with an overall highly engineered group velocity dispersion (GVD) shifted to the mid-IR wavelengths region. By injecting 100 fs hyperbolic-secant input pulses delivered by available tunable optical parametric oscillator (OPO) system at the pump wavelength of 3.389 μm, we obtain a broadband coherent mid-IR SC generated in only 1 mm-long PCF with a peak power of 8.8 kW. An ultralarge mid-IR bandwidth extending from 1000 to 7200 nm is generated with more than 60% of the total power which is available beyond 3 μm. The proposed hybrid PCF structure shows to be very promising for designing new compact, stable and powerful SC fiber laser sources in the long mid-IR wavelength region.

The paper discuss about accelerated ageing of optical fiber elements in their burdened with gamma radiation. In addition to the destruction of coating materials, gamma radiation has its effect on the internal structure of the optical fiber. It is necessary to specify the changes in the optical coupler and find out why these changes occur.

This article contains experimental measurement of the impact of gamma radiation Cobalt-60 on the optical couplers of various split performance ratio. The couplers were exposed to gradually increasing doses of 60Co. Measurements are focused on the overall distribution of the energy in the core and cladding various branches of SM optical fiber couplers. This article focuses on applied research and experimental development of resources for safety operation of optical networks since monitoring of ageing substantially contributes to its security. It addresses issues of accelerated ageing of optical fiber elements in their burdened with gamma radiation. How does radiation energy of gamma radiation influence optical network elements? This effect is explored just very little bit and is yet another unanswered question. In addition to the destruction of coating materials, gamma radiation has its effect on the internal structure of the optical fiber. It is necessary to specify the changes in the optical coupler and find out why these changes occur. This article contains experimental measurement of the impact of gamma radiation Cobalt-60 on the optical couplers of various split performance ratio. Optical passive components, couplers, were exposed to gradually increasing doses of ⁶⁰Co. Measurements are focused on the overall distribution of the energy of LP₀₁ mode in the core and cladding various branches of SM optical fiber couplers. Graphical and mathematical detect changes in the dissemination of energy coupler after single doses of gamma radiation are useful to understand the phenomenon of accelerated ageing elements of optical networks in environments with an increased incidence of radiation energy. Keywords: 2-D view, 3-D view, coupler, gamma radiation, Cobalt-60, ageing, energy

100 nm Broadly tunable InGaAsP/InP asymmetric multiple quantum well (AMQW) ridge waveguide laser diodes has limited applications because of its low output power problem. The current injection efficiency of such lasers in average is 18 %. A FlexPDE simulation model showed that the main reason for this poor current injection efficiency is the ridge structure. Since the ridge structure is an essential part of these type of laser diodes, we proposed a forced electrical confinement method to improve current injection efficiency of these lasers. The simulation data for the proposed method showed that it is possible to increase the current injection efficiency up to 90 %. The simulation data also, showed a reduction of nearly 10°C in the maximum temperature of these devices compared with original AMQW devices. This temperature improvement is significant and can lead to a significant improvement of the laser output power. Experimental data however, give less optimistic results. The experimental data did show improvement in the current injection efficiency but also showed creation of recombination centers that reduce the temperature and power improvement. The proposed method can be efficient but a passivation technique needs to be developed for these devices.

A rectangular core photonic crystal fiber design in As₂Se₃ chalcogenide glass has been reported for mid-infrared supercontinuum generation. The structural parameters have been tailored for all normal dispersion profile. The proposed structure possesses nonlinearity (Υ) as large as 20956 W-1 km^-1 at 2800 nm wavelength with very low and flat dispersion of -2.38 ps/(nm×km). We have generated supercontinuum spectra spanning 1480 – 9990 nm using only 4 mm length of proposed photonic crystal fiber pumped with femtosecond optical pulses of peak power of 500 W at 2800 nm.

Recently, photonic crystal fibers have attracted significant attention for their applications in optical fiber communication systems. In some polarization sensitive applications photonic crystal fibers with single-mode and single-polarization are desirable. In this paper, a rectangular-core single-mode single-polarization large-mode-area photonic crystal fiber structure has been designed based on higher order mode filtering. The single-polarization is obtained with asymmetric design and introducing different loss for x-polarization and y-polarization of fundamental mode. Single-polarization single-mode operation of a highly bi-refringent photonic crystal fiber is investigated in detail by using a full-vector finite-element- method with anisotropic perfectly-matched-layer. At optimized parameters, the confinement loss and effective-mode-area is obtained as 0.9 dB/m and 927 μm² for x-polarization as well as 12.53 dB/m and 921 μm² for y-polarization of fundamental mode respectively at 1.55 μm. Therefore, 1.6 m length of fiber will be sufficient to get x-polarized fundamental mode with effective-mode-area as large as 927 μm².

A novel sensor for high-temperature measurement using Fiber Bragg grating (FBG) has been designed and simulated. The sensor works based on measurement of the shift in Bragg wavelength that corresponds to the temperature induced strain by making use of a mechanical transducer. The transducing element provides temperature dependent strain on FBG by means of differential linear thermal expansion of two different ceramic materials: Alumina and Silicon Carbide. The designed sensor can measure the temperatures from 20°C to 1500°C.

Transparent and conductive Indium Tin Oxide (ITO) films were grown on borosilicate glass substrate by radio frequency (RF) magnetron sputtering process. The effects of sputtering parameters e.g. substrate temperature and RF power levels on electrical, optical and structural properties were examined. The crystallinity, conductivity and optical transparency of the films were evaluated by X-ray diffraction, four-point probe measurement, laser ellipsometry, and optical spectroscopy. The surface roughness and grain size of the films were also investigated using scanning probe microscopy. This paper reports the non-monotonical dependence of substrate temperature on the nanostructure and phases and the complex impact of RF power levels to the conductivities and the optical properties. The critical role of oxygen partial pressure on the energy bandgaps is also inferred.

We analyze laser-induced periodic structure developing in a semiconductor under the condition of both optical bistability existence and action of 2D external electric field. Optical bistability occurs because of nonlinear dependence of semiconductor absorption coefficient on charged particles concentration. The electron mobility, diffusion of electrons and laser-induced electric field are taken into account for laser pulse propagation analyzing. 2D external electric field together with electric field, induced by free electrons and ionized donors, governs the charged particle motion. Under certain conditions, the additional positive inverse loop between electron motion and electric field, caused by redistribution of free charged particles, appears. As a result, the helical wave for free charged particle concentration of electron-hole plasma in semiconductor develops under the electric field action.

For computer simulation of a problem under consideration, a new finite-difference scheme is proposed. The main feature of proposed method consists in constructed two-step iteration process. We pay a special attention for calculation of initial functions distributions. For their calculation we solve the set of 2D stationary partial differential equations by using additional iteration process that is similar to the iteration process, applied for the main problem solution.

Microstructured fibers have recently become popular due to their numerous applications for fiber lasers,¹ super-continuum generationi² and pulse reshaping.³ One of the most important properties of such fibers that is taken into account is its dispersion. Fine tuning of the dispersion (i.e. dispersion management) is one of the crucial peculiarities of the photonic crystal fibers (PCFs)⁴ that are particular case of the microstructured fibers.

During last years, there have been presented various designs of the PCFs possessing specially-designed dispersion shapes. ^5-7 However, no universal technique exists which would allow tuning the PCF dispersion without using optimization methods.

In our work, we investigate the sensitivity of the PCF dispersion as respect to variation of its basic parameters. This knowledge allows fine-tuning the position of local maximum of the PCF dispersion while maintaining other properties unchanged.

The work is organized as follows. In the first section we discuss the dispersion computation method that is suitable for the global sensitivity analysis. The second section presents the global sensitivity analysis for this specific case. We also discuss there possible selection of the variable parameters.

We numerically investigated optical properties, including evanescent intensity ratio (EIR), effective refractive index (N_eff), dispersion coefficient (D), and mode area (A_eff) of the silicon nitride trench waveguides fabricated by using conventional lithography. The waveguides are etched 3 μm deep with potassium hydroxide for triangle and trapezoidal waveguides, which is then followed by 3 μm thermal oxidation and 725 nm silicon nitride deposition. The waveguide with 725 nm thickness has an EIR peak of 0.025 when its bottom width W_btm equals 0.65 μm. A thinner waveguide has higher evanescent intensity ratio, which can be used in sensing applications. The locations of EIR peaks correspond to the quasi-TM and TE mode boundary. Narrower waveguides mainly support quasi-TM modes, whereas wider waveguides can support only TE modes. As the waveguide width increases, higher orders of TE modes emerge. In addition, a boundary of TE single mode and multimode can also be linearly curve fitted, according to the starting points of TE higher modes, in order to provide the single mode condition of the waveguide. The waveguide dispersion can be engineered to be in the anomalous region while at the same time remain close to zero. The waveguide with 725 nm thickness and 0.2 μm bottom width has its anomalous dispersion region between the wavelength of 1356 nm and 1462 nm. The mode area decreases with increasing waveguide width. This is the first time we have studied the mode properties of trench waveguides systematically. The waveguide will find more applications in sensing and nonlinear fields with the help of this mode analysis.

In this paper, we have calculated the highly efficient generation of the slow light based on the Stimulated Brillouin scattering (SBS) in a small core As₂Se₃ chalcogenide PCF. A Brillouin gain coefficient, g_B. of 9.05 10-9 m.W-1 is found around the acoustic frequency of 8.08 GHz in small core diameter of 1.69 μm with 1.5 μm² effective mode area at 1550 nm. A Brillouin gain of 77.3 dB was achieved with only 10 mW pump power in a 10-m fiber length, which leads to the optical time delay of 94 ns. In terms of the proposed figure of merit, it shows 2.77 dB/mW/m which is about 110 times more efficient than conventional single-mode fibers. These fibers are expected to have potential applications in realization of compact slow light devices.

Evanescent wave absorption spectroscopy (EWAS) based sensors offer a number of unique advantages which include compatibility with remote optical sensing, simplicity of sensor design, low cost of sensing elements, and compatibility with harsh environment sensing applications. A number of different sensor-materials exist for the sensing of various chemical and environmental parameters and signal-to-noise ratios (SNRs) for such devices are dictated by a complex interplay of device design and sensing material selection for the EWAS configuration. In this work, we report that one effective way to optimize SNRs for a fixed sensor device / material design is through unique interrogation methods including angular selectivity in the sensor interrogator. We theoretically illustrate the origins of the signal optimization technique, and demonstrate feasibility using an EWAS sensor designed for harsh-environment pH sensing.

In this paper, a nanosecond speed KTN beam deflector is presented. The beam deflector is based on the combination of pre-injected space charge field and high speed (nanosecond) switching field. A beam deflection speed on the order of nanosecond was demonstrated, which was fastest beam deflection speed reported so far. The experimentally results confirmed that the speed limitation of KTN beam deflector was not limited by the electro-optic (EO) effect itself but the driving electric source and circuit. With a faster speed driving source and circuit, it is possible to develop GHz frequency beam deflector.

In recent years, the ever-increasing demand for high-capacity transmission systems has driven remarkable advances in technologies that encode information on an optical signal. Mode-division multiplexing makes use of individual modes supported by an optical waveguide as mutually orthogonal channels. The key requirement in this approach is the capability to selectively populate and extract specific modes. Optical supersymmetry (SUSY) has recently been proposed as a particularly elegant way to resolve this design challenge in a manner that is inherently scalable, and at the same time maintains compatibility with existing multiplexing strategies.

Supersymmetric partners of multimode waveguides are characterized by the fact that they share all of their effective indices with the original waveguide. The crucial exception is the fundamental mode, which is absent from the spectrum of the partner waveguide. Here, we demonstrate experimentally how this global phase-matching property can be exploited for efficient mode conversion. Multimode structures and their superpartners are experimentally realized in coupled networks of femtosecond laser-written waveguides, and the corresponding light dynamics are directly observed by means of fluorescence microscopy. We show that SUSY transformations can readily facilitate the removal of the fundamental mode from multimode optical structures. In turn, hierarchical sequences of such SUSY partners naturally implement the conversion between modes of adjacent order. Our experiments illustrate just one of the many possibilities of how SUSY may serve as a building block for integrated mode-division multiplexing arrangements. Supersymmetric notions may enrich and expand integrated photonics by versatile optical components and desirable, yet previously unattainable, functionalities.

In this paper, based on the theory of dynamic waveguiding effect in nanodisordered KTN crystals, a detailed design and implementation of a super broadband 1x2 high speed waveguide switch is presented. The important waveguide parameters, including the dimension, the refractive index distribution, and the electric field distribution within the waveguide are quantitatively simulated and analyzed. An experimental verification of switching effect based on the design is also conducted, which confirmed the design. The broadband and high speed nature of such kind of switch can play a key role in data center networks and cloud computing, which needs low power consumption and high speed switches.

In this paper, we have proposed a design for slow light effect in pinch photonic crystal waveguide. The design consists of two dimensional triangular arrangements of air holes in silicon on insulator substrate. From the calculations it has been found out that for the proposed structure the group index is high and group velocity dispersion is low. The confinement of light in the pinch waveguide with slow light effect can be a strong candidate for sensor applications.

In this essay, we investigate the higher order dispersion effects on supercontinuum (SC) generation in microstructure fibers by studying the temporal and frequency dependence of the ejected pulse. We also investigate the soliton formation and spectrum broadening. In these processes, we observed dispersive wave generated due to soliton fission. Here, we solve nonlinear Schrodinger equation by split step Fourier method.

Geometrical shaping of non-adiabatic single tapers is used to modify the filtering characteristics. The fiber tapers are shaped by successive tapering. The taper shaping produces deeper rejection bands. As an application of the shaped tapers, fluidic temperature sensing cells were fabricated. In a first case, the wavelength shift of a single rejection band was monitored, showing a nonlinear response and low sensitivity to temperature changes. In a second case, a shaped taper fluidic cell containing two rejection bands was used, and the wavelength shift of the half intensity points of the transmission band (between the rejection bands) was taken as a measure of the temperature change. In this case, the fluidic cell showed a linear sensitivity of 481.9 pm/°C in a temperature range of 25°C-60°C.

A 3 × 3 free-space optical router, which comprises optical switches and polarizing beam splitter (PBS) and based on crossbar network, is proposed in this paper. A control algorithm for the 3 × 3 free-space optical router is also developed to achieve rapid control without rearrangement. In order to test the performance of the network based on 3 × 3 free-space optical router and that of the algorithm developed for the optical router, experiments are designed. The experiment results show that the interconnection network based on the 3 × 3 free-space optical router has low cross talk, fast connection speed. Under the control of the algorithm developed, a non-block and real free interconnection network is obtained based on the 3 × 3 free-space optical router we proposed.

Commonly, one dimensional construct has a restriction of viewing angle. We report a new, simplistic strategy to Particle Photonic Crystal: an ellipsoidal block copolymer nanoparticles. It has a wider viewing angle and is easier to make. We made a particle of photonic crystal based on Poly Styrene-block-Poly-2-Vinyl Pyridine(PS-b-P2VP) in chloroform. After using Poly Vinyl Alcohol(PVA), it was in state of emulsion and self assembly method followed afterwards. In the first trial, we observed particle structure variation according to the difference in molecular weight such as 52k-57k, 75k-66.5k, 102k-97k. Afterwards, we exhibited how particle structure change by the addition of swelling solution (Alcohol). The molecular structure of particle photonic crystal was investigated by Transmission Electron Microscope. The color was measured by color-difference meter.

Scientists have recently discovered that the ageing process of optical elements is faster than it was originally anticipated. It is mostly due to the multiple increases of the optical power in optical components, the introduction of wavelength division multiplexers and, overall, the increased flow of traffic in optical communications. This article examines the ageing process of optical couplers and it focuses on their performance parameters. It describes the measurement procedure followed by the evaluation of the measurement results. To accelerate the ageing process, gamma irradiation from ⁶⁰Co was used. The results of the measurements of the optical coupler with one input and eight outputs (1:8) were summarized. The results gained by measuring of the optical coupler with one input and four outputs (1:4) as well as of the optical couplers with one input and two outputs (1:2) with different split ratios were also processed. The optical powers were measured on the input and the outputs of each branch of each optical coupler at the wavelengths of 1310 nm and 1550 nm. The parameters of the optical couplers were subsequently calculated according to the appropriate formulas. These parameters were the insertion loss of the individual branches, split ratio, total losses, homogeneity of the losses and directionalities alias cross-talk between the individual output branches. The gathered data were summarized before and after the first irradiation when the configuration of the couplers was 1:8 and 1:4. The data were summarized after the third irradiation when the configuration of the couplers was 1:2.

Thermal dissipation had an important influence in the effect and life of light emitting diodes (LED) because it enables transfer the heat away from electric device to the aluminum plate that can be used for heat removal. In the industrial processing, the quality of the thermal dissipation decides by the gumming technique between the PCB and aluminum plate. In this study, we fabricated double layer ceramic thin films of diamond like carbon (DLC) and alumina nitride (AlN) by vacuum sputtering soldered the substrate of high power light emitting diodes (HPLED) light to check the heat conduction. The ceramic dielectric coatings were characterized by several subsequent analyses, especially the measurement of real work temperature. The X-Ray photoelectron spectroscopy (XPS) patterns reveal those ceramic phases were successfully grown onto the substrate. The work temperatures show DLC and AlN films coating had limited the heat transfer by the lower thermal conductivity of these ceramic films. Obviously, it hadn’t transferred heat and limited work temperature of HPLED better than DLC thin film only.

This paper is focusing on simulation and analyzed of S-band multi-wavelength Brillouin–Raman fiber laser performance utilizing fiber Bragg grating and Raman amplifier in ring cavity by using Optisystem software. Raman amplifieraverage power model is employed for signal amplification. This laser system is operates in S-band wavelength region due to vast demanding on transmitting the information. Multi-wavelength fiber lasers based on hybrid Brillouin-Raman gain configuration supported by Rayleigh scattering effect have attracted significant research interest due to its ability to produced multi-wavelength signals from a single light source. In multi-wavelength Brillouin–Raman fiber, single mode fiber is utilized as the nonlinear gain medium. From output results, 90 % output coupling ratio has ability to provide the maximum average output power of 43 dBm at Brillouin pump power of 20 dBm and Raman pump power of 14 dBm. Furthermore, multi-wavelength Brillouin–Raman fiber laser utilizing fiber Bragg grating and Raman amplifier is capable of generated 7 Brillouin Stokes signals at 1480 nm, 1510 nm and 1530 nm.

In this paper, the two-center recording with 633nm recording and 465nm sensitizing is performed in doubly-doped LiNbO₃:Fe:Ru and LiNbO₃:Ce:Ru crystals, respectively. The investigation for transmission spectra shows that the better transmission can be found from 400nm to 700nm in LiNbO₃:Ce:Ru crystals. Performance measures, such as diffraction efficiency, recording sensitivity, are calculated and compared according to the time evolution curves of diffraction efficiency. The results show that the high recording sensitivity and dynamic range can be obtained in LiNbO₃:Fe:Ru crystal. The scattering noise in LiNbO₃:Ce:Ru and LiNbO₃:Fe:Ru is investigated, the results show that the lower noise can be observed in LiNbO₃:Ce:Ru crystal.

A tunable wavelength erbium doped fiber ring laser, based on mechanically induced long-period fiber gratings (MLPFG) is presented. The laser was tuned applying pressure over the MLPFG, in order to control this, pressure is applied over a plate with periodic grooves that has a short length, this pressure is applied by a digital torque tester, as a result tunable effect is observed. The grooves have a period of 630μm 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 thermal stability, similar to high cost photoinduced long period gratings. In this work, by pressure increment distributed over the MLPFG from 0.20 lb-in² to 0.50 lb-inμ, tuned operation range of 10nm was observed and single line emission was tuned between C and L telecommunications bands. According to the stability analysis the signal to noise ratio and linewidth observed were 35dB and 0.2nm respectively.

The design, fabrication and measurement of a cylindrical fiber coil structure is presented that has applications for compact fiber-optic amplifiers. A multimode fiber is used as a surrogate for a dual clad, rare-earth doped fiber for coil fabrication and optical testing. A ray trace algorithm, written in Python, was used to simulate the behavior of light travelling along the waveguide path. An in-house fabrication method was developed using 3D printed parts designed in SolidWorks and assembled with Arduino-controlled stepper motors for coil winding. Ultraviolet-cured epoxy was used to bind the coils into a rigid cylinder. Bend losses are introduced by the coil, and a measurement of the losses for two coil lengths was obtained experimentally. The measurements confirm that bend losses through a multimode fiber, representative of pump light propagating in a dual-clad rare-earth doped fiber, are relatively wavelength independent over a large spectral range and that higher order modes are extinguished quickly while lower order modes transmit through the windings with relatively low loss.

We report on the ongoing investigation of magnetron sputtered germanium on silicon for photonics applications. Direct current (DC) magnetron sputtering has been used to deposit germanium layers on silicon at low growth temperatures and medium range vacuum levels. Standard photolithography has been used to make germanium photodetectors for the 1550 nm wavelength range. Electrical characterization, more specifically current-voltage measurements indicate that the devices function as intended. Sputtered silicon waveguides have also been fabricated and evaluated for possible applications in photonics integration. The sputtering-based developments in our present research are expected to provide for a flexible and economically viable manufacturing process for such devices.

The memristor element for random access memory (resistance random access memory - ReRAM) was developed and investigated. The developed structure consists of a Schottky diode (1D) based on Pt/ZnO:Ga/ZnO/Pt heterostructure and a memristor (1R) based on Pt/ZnO:Ga/ZnO/ZnO:Li/Pt heterostructure. Thus the unipolar memristor memory element of 1D1R type was obtained. The heterostructures were produced by the electron-beam vacuum deposition method. The laboratory samples of the memory elements were prepared and their characteristics were studied. The proposed device has a high stability and withstands 1000 switching cycles without derating.

A bidirectional ROF configuration has been proposed and developed to transmit 80 channels HDTV signal over 80 km SMF integrating mutually injection locking, optical carrier suppression (OCS) and remodulation techniques. LiNbO₃ Mach-Zehnder modulator is used at transmitter end to realize the OCS scheme by mixing two complementary signals of 30GHz. RSOA is deployed at the user end to reuse and remodulate the downstream HDTV signal to upstream transportation over same 80km fiber link. The uplink and downlink transmission performances are observed and analyzed by excellent eye-diagram and low bit error rate values.

A bidirectional and simultaneous transmission of Ethernet, FTTX services through single optical carrier wavelength employing polarization multiplexing technique in the transmitter end and the user end. 10 Gbps and 2.5 Gbps datarates are transmitted over 50 km single mode fiber employing POLMUX technique at OLT and ONU to provide Ethernet and FTTX services concurrently to the user. Reflective semiconductor optical amplifier is used to reuse and remodulate the downlink signal to uplink transmission. The upstream and the downstream transmission performances are observed by the bit error rate values and the eye diagrams obtained by the BER analyzer.

An encoding algorithm to identify the fringe orders for Fourier transform profilometry is described. Phase unwrapping is then performed with reference to the encoding algorithm. Even though the inspected object is colorful or sensitive to the reflectance variation, unwrapping can be performed without ambiguity. The computation cost is very low, and its unwrapped errors can be confined in a local area.

A non-scanning method to describe the 3D profile of a metal surface is proposed. A fringe pattern is posited in front of the metal surface. A virtual image of the fringe pattern is formed behind the metal surface. Fringes on the virtual image are deformed by topography of the metal object. Thus, phase of the deformed fringes is desirable to retrieve the profile of the metal surface.

We present a fringe projection system embedded into an endoscope to describe the absolute shape of an inspected object. A fringe pattern generated by launching incoherent light waves into a volume hologram is projected on the inspected surface. The endoscope observes the projected fringes at another point of view. Fringes on the obtained image are deformed both by the topography of the object, and are analyzable to retrieve the 3D shape.

A reliable image processing method is provided to enhance the accuracy of the scanning fringe projection technique. Noises and errors for surfaces on the edge area can be efficiently detected and reduced. To accurately describe the shape of a complicated object is available.