This PDF file contains the front matter associated with SPIE Proceedings Volume 8627, including the Title Page, Copyright Information, Table of Contents, and the Conference Committee listing.

We have proposed an optical spectrum control circuit that realizes various kinds of signal processing in the optical domain using a silica-based planar lightwave circuit including arrayed-waveguide gratings. In order to obtain a flat transmission spectrum required for processing an optical signal that has a continuous spectrum, the number of the spectral output waveguides is set more than the number of waveguides in the waveguide array. In this study, we demonstrated a phase error compensation and obtained the flat transmission spectrum with ripples below 0.9 dB. We also demonstrated a tunable bandwidth operation as an example of the spectral amplitude control and a variable pulse delay operation as an example of the spectral phase control, respectively. In the tunable bandwidth operation, the passband characteristic of the minimum bandwidth of 5-GHz and tunable pass-band characteristics with different center frequencies with about 20-dB extinction ratio were obtained. In the variable delay operation, pulse delays equal to calculated values could be observed with some phase settings.

Bismuth germanate is a well known scintillator material. It is also used in nonlinear optics, e.g. for building Pockels cells, and can also be used in the fabrication of photorefractive devices. In the present work planar optical waveguides were designed and fabricated in eulytine (Bi₄Ge₃O₁₂) and sillenite (Bi₁₂GeO₂₀) type bismuth germanate crystals using single- and double-energy irradiation with N⁺ ions in the 2.5 < E < 3.5 MeV range. Planar waveguides were fabricated via scanning a 2 mm × 2 mm beam over the waveguide area. Typical fluences were between 1 • 10¹⁵ and 2 • 10¹⁶ ions/cm². Multi-wavelength m-line spectroscopy and spectroscopic ellipsometry were used for the characterization of the ion beam irradiated waveguides. Waveguide structures obtained from the ellipsometric data via simulation were compared to N⁺ ion distributions calculated using the Stopping and Range of Ions in Matter (SRIM) code. M-lines could be detected up to a wavelength of 1310 nm in the planar waveguide fabricated in sillenite type BGO, and up to 1550 nm in those fabricated in eulytine type BGO.

In this paper we review our work in the field of heterogeneous integration of III-V semiconductors and non-reciprocal optical materials on a silicon waveguide circuit. We elaborate on the heterogeneous integration technology based on adhesive DVS-BCB die-to-wafer bonding and discuss several device demonstrations. The presented devices are envisioned to be used in photonic integrated circuits for communication applications (telecommunications and optical interconnects) as well as in spectroscopic sensing systems operating in the short-wave infrared wavelength range.

In this work, both the design and experimental characterization of an InP photonic integrated circuit (PIC) working as a receiver for frequency-modulated microwave photonic links (MPWL) are presented. The PIC consists of three ring-assisted Mach-Zehnder interferometer (RAMZI) filters acting together as a complementary frequency discriminator, and includes a high-bandwidth balanced photodiode for on-chip signal detection. This is, to the best of our knowledge, the first PIC of this kind to be integrated in an active platform, and the first to include optical detectors. Designed as linear filter in optical intensity, the chip features SFDR values in the range of 78 dB.Hz^2/3 and RF gains of -46 dB, partially limited by the high optical coupling losses of our experimental setup. Possible paths for further improvement of link figures of merit are also discussed.

In this work an integrated tunable optofluidic liquid core-liquid cladding (L2) optical fiber is presented. The device has been realized by exploiting an innovative three-dimensional hydrodynamic focusing scheme. A tunable circular liquid core has been obtained that is located in the center of the channel, regardless of the flow rate ratio of the cladding and core liquids. This circular geometry allows a more simple control of the optical property of the beam and the input and output coupling with standard optical fiber. A liquid core with a tunable diameter ranging from 45.3 to 11.2 μm has been successfully obtained.

We propose and demonstrate a new integrated polarization splitter made by ion exchange on glass operating at a wavelength of 1.55 μm. The design is based on an asymmetric Y-junction with one output branch supporting only the TE mode. Cross-talk lower than -30.0 dB in TM mode has been achieved over a wavelength range of 80 nm. Values lower than -10.0 dB for the TE mode were demonstrated over the same bandwidth with an optimum of -19.8 dB at 1.54 μm. The experimental results are in good agreement with simulations. We measured insertion losses of 6.5 dB in both modes.

It is shown that microsphere-chain waveguides have strong polarization-dependent attenuation properties that can be used for developing passive filters of radially polarized beams. By using numerical modeling, it is demonstrated that the principle of operation of such devices is based on filtering periodically focused modes in chains of dielectric spheres occurring for a narrow range of indices of refraction 1.7<n<1.8. It is shown that for 10- and 20-sphere long chains a degree of radial polarization in excess of 0.8 and 0.9, respectively, can be obtained that allows developing novel polarization components with the light focusing capability.

In this paper we present recent results obtained in the area of monolithically integrated modelocked semiconductor laser systems using generic InP based integration platform technology operating around 1550nm. Standardized components defined in this technology platform can be used to design and realize short pulse lasers and optical pulse shapers. This makes that these devices can be realized on wafers that can contain many other devices. In the area of short pulse lasers we report design studies based on measured optical amplifier performance data. This work has the ultimate goal to establish a library of widely applicable short pulse laser designs. Such lasers can include components for e.g. wavelength control. An important boundary condition on the laser design is that the laser can be located anywhere on the InP chip. In the area of pulse shaping we report on a 20 channel monolithic pulse shaper capable of phase and amplitude control in each channel. Special attention is given to the calibration of the phase modulator and amplifier settings. Pulse compression and manipulation of pulse generated from modelocked semiconductor lasers is demonstrated using a 40 GHz quantum dash modelocked laser.

A passively Q-switched distributed-Bragg-reflector laser made in glass integrated optics technology, and operating around 1030 nm, is designed, realized and investigated. The laser is formed by an ion-exchanged single mode waveguide realized in an Ytterbium doped phosphate glass. The Q-switching behavior is obtained by hybridizing a saturable absorber film on the waveguides. This allows the realization of a short and simple laser cavity having both pulsed and a narrow linewidth emission. Its experimental characterization leads to the observation of a stable repetition rate of 12.5 kHz and a stable pulse duration of 9.2 ns FWHM.

This paper presents a study (simulations) of coupling losses between adjacent waveguides made of tellurite glasses. These waveguides are designed to perform parametric amplifiers (PAs). PAs have some advantageous characteristics over the other optical amplifiers: they have broadband amplification bandwidth (depending on the dispersive characteristics of the waveguide), other all-optical functionalities, and can work at ultra-high bit rates (Pbit/s). PAs are based on the nonlinear phenomena of phase matched four-wave mixing between a strong pump and a weak signal. The parametric gain increases with the waveguide length, the pump power and the nonlinear coefficient of the waveguide. The best alternative to maximize the parametric gain is to reduce the pump power as much as possible, increasing the waveguide length and/or the nonlinear coefficient of the waveguide. The latter parameter can be enhanced by increasing the nonlinear refractive index of the material (n₂) or by reducing the waveguide effective area. Here we perform waveguides made of tellurite because these glasses have an n₂ that goes up to 30 x 10^-19 m²/W. On the other hand, the waveguide length can be increased by using an Archimedean spiral design. This geometry allows obtaining long waveguides (~1 m) within a small area. Using the Finite Element Method we study the separation distance between adjacent waveguides in order to obtain coupling lengths higher than the waveguide length (total losses < 2 dB/m). The waveguide dimensions are optimized to obtain a monomode waveguide with dispersive characteristics to perform PAs (around ~1550 nm spectral region).

In recent years silicon photonics has become a mature technology enabling the integration of a variety of optical and optoelectronic functions by means of advanced CMOS technology. While most efforts in this field have gone to telecom and datacom/interconnect applications, there is a rapidly growing interest in using the same technology for sensing applications, ranging from refractive index sensing to spectroscopic sensing. In this paper the prospect of silicon photonics for absorption, fluorescence and Raman spectroscopy on-a-chip will be discussed. To allow spectroscopy in the visible and near infrared the silicon photonics platform is extended with silicon nitride waveguides.

A leaky loop Fourier Transform spectrometer is presented in 700-1000nm spectral bandwidth. This integrated optic spectrometer is made without moveable parts. The contrast and the shape of the interferogram created at the end of the component are controlled by the gap evolution between the bend waveguide and the planar waveguide. Glass ion exchange has been chosen to obtain a high fringe contrast. A linear camera set directly at the end of the component allows interferences capture from 780nm to 850nm and the light vertical scattering due to the waveguides surface roughness is used to characterize the optical loop behavior.

We demonstrate a device which can do multiplexed detection of two different chemicals on one chip by using infrared absorption spectroscopy. The signature of Trichloroethylene(TCE) and xylene in water enable multiplexed detection on one chip. We use the slow light effect in the photonic crystal design which enhances the absorption of the analytes by a factor of 30 as demonstrated by our previous works. In order to match the absorption peaks of these two analytes, photonic crystal slow light regions are designed at 1644nm and 1674nm with a SU8 cladding on top. Multiplexed detection is enabled by using a multimode interference (MMI) optical power splitter at the input, which divides optical power into two arms, and Y combiner at the output. Consequently, the absorption of these two chemicals can be enhanced by the slow light effect. The MMI structure and Y combiner also enable the multiplexed detection of two analytes on one chip.

We present a new integrated optical sensor for absorption spectroscopy in a hostile environment, based on a nanochannel waveguide structure in glass. The nanochannel waveguide is made by bonding two ion-exchanged borosilicate glass wafers, one of them being etched by reactive ion etching to create a 100 nm deep fluidic channel. Typical fluid/light interaction factors of 2.3 % can be achieved inside a 7.4 pL volume of fluid, over a 550 nm bandwidth, surmounting evanescent wave sensors in terms of confinement efficiency and allowing spectrometric measurements. Absorption measurements have been performed on hexahydrate neodymium nitrate in nitric acid solutions of various concentrations leading to a minimum detectable absorption coefficient of 0.57 cm^-1, which can be further decreased by implementing low bending-loss spiral-like nanochannel waveguides.

This works demonstrates the use of suspended core optical fibers as a platform for explosives detection in solution using Raman spectroscopy. This architecture combines small sampling volumes with long light-analyte interaction lengths, resulting in identification of minute quantities of explosives in solutions. In addition, the Raman signature of the solvent is used as an internal calibration standard to allow quantification of the detected molecule. Our results show detection of sub-microgram amounts of hydrogen peroxide (H₂O₂) in aqueous solution, a molecule difficult to detect as it lacks the nitroaromatic units, characteristic of trinitrotoluene (TNT) based explosives, which are usually targeted by traditional optical methods such as fluorescence. The same platform without any modifications can also be used to identify and quantify comparable amounts of 1,4-dinitrobenzene (DNB), a substitute molecule for TNT. These results highlight the capability of suspended-core fibers as small, cost-efficient and low-volume explosives sensors.

Whispering-Gallery-Mode (WGM) resonators are emerging as an excellent platform to study optical phenomena resulting from enhanced light-matter interactions due to their superior capability to confine photons for extended periods of time. The monolithic fabrication process to achieve ultra-high-Q WGM resonators without the need to align multiple optical components, as needed in traditional design of resonators based on precise arrangement of mirrors, is especially attractive. Here we explain how to process a layer of thin film doped with optical gain medium, which is prepared by wet chemical synthesis, into WGM structures on silicon wafer to achieve arrays of ultra-low threshold on-chip microlasers. We can adjust the dopant species and concentration easily by tailoring the chemical compositions in the precursor solution. Lasing in different spectral windows from visible to infrared was observed in the experiments. In particular, we investigated nanoparticle sensing applications of the on-chip WGM microlasers by taking advantages of the narrow linewidths and the splitting of lasing modes arising from their interactions with nano-scale structures. It has been found that a nanoparticle as small as ten nanometers in radius could split a lasing mode in a WGM resonator into two spectrally separated lasing lines. Subsequently, when these lasing lines are photo-mixed at a photodetector a heterodyne beat note is generated which can be processed to signal the detection of individual nanoparticles. We have demonstrated detection of virions, dielectric and metallic nanoparticles by monitoring the changes in this self-heterodyning beat note of the split lasing modes. The built-in self-heterodyne method achieved in this monolithic WGM microlaser provides an ultrasensitive scheme for detecting and measuring nanoparticles at single particle resolution, with a theoretical detection limit of one nanometer.

Developing optical resonators with high quality factors, small mode volumes, and high refractive index contrast is important for many integrated optics and communications applications. High quality factors and small mode volumes are especially desirable to maximize the circulating intensity and Purcell factor for laser applications. However, controlling an optical resonator’s mode volume and refractive index contrast can be difficult as they depend primarily on the inherent material properties of the resonator. One approach to reduce mode volume and control refractive index contrast is to apply high refractive index polymer coatings. However, polymer coatings are not compatible with all fabrication processes and not as robust as silica and silicon. Recently, we developed and characterized high refractive index silica films containing small amounts of titanium dopant. The silica films are fabricated using a sol gel method with methyl triethoxysilane (MTES) and tetraethyl orthosilicate (TEOS) precursors. Depending on the amount of titanium added, the refractive index of the resulting film can be tuned from 1.44 to 1.62, as measured by spectroscopic ellipsometry. By spin coating these high index silica films onto silica toroid resonators, we experimentally and numerically obtain a significant reduction in mode volume while maintaining high quality factors. Additionally, the presence of the high refractive index coating allows tuning of the circulating light’s position, shape, and interaction with the coating. Therefore, these high refractive index films offer a useful and more robust method to optimize the properties of optical devices for communications and integrated optics applications.

To become a competitor to replace CMOS-electronics for next-generation data processing, signal routing, and computing, nanoplasmonic circuits will require an analogue to electrical vias in order to enable vertical connections between device layers. Vertically stacked nanoplasmonic nanoring resonators formed of Ag/Si/Ag gap plasmon waveguides were studied as a novel 3-D coupling scheme that could be monolithically integrated on a silicon platform. The vertically coupled ring resonators were evanescently coupled to 100 nm x 100 nm Ag/Si/Ag input and output waveguides and the whole device was submerged in silicon dioxide. 3-D finite difference time domain simulations were used to examine the transmission spectra of the coupling device with varying device sizes and orientations. By having the signal coupling occur over multiple trips around the resonator, coupling efficiencies as high as 39% at telecommunication wavelengths between adjacent layers were present with planar device areas of only 1.00 μm². As the vertical signal transfer was based on coupled ring resonators, the signal transfer was inherently wavelength dependent. Changing the device size by varying the radii of the nanorings allowed for tailoring the coupled frequency spectra. The plasmonic resonator based coupling scheme was found to have quality (Q) factors of upwards of 30 at telecommunication wavelengths. By allowing different device layers to operate on different wavelengths, this coupling scheme could to lead to parallel processing in stacked independent device layers.

Tilted Bragg gratings (TBGs) have been shown to have a number of practical uses in planar geometries, demonstrating polarization capabilities and allowing excitation of surface plasmons. Fabrication and characterization of TBGs has been carried out in silica-on-silicon waveguides to highlight potential planar applications. An initial investigation into the coupling behaviour of TBGs has been undertaken, with greater than -20 dB coupling achieved for even small angle gratings (5 °). Experimental analysis of these TBG systems provides insight into future applications of the planarized devices.

Direct UV Grating Writing (DGW) is an attractive technique for fabricating integrated Bragg grating devices in a silica-on- silicon platform. In this work we propose and demonstrate a novel phase modulated DGW method using an Electro- Optical Modulator for planar Bragg grating fabrication that offers improved performance. This new approach has allowed us to construct Bragg gratings with versatile structures such as phase shifts and apodization profiles. Simple uniform gratings, single and multiple phase shifted gratings, apodized gratings and chirped gratings have been made in this method; using grating detuning and this new phase controlled method we have shown that planar Bragg gratings can be written among 700 nm wavelength range on a single chip exclusively using software control.

The applications of Bragg-grating concepts in a multitude of photonic device functionalities are well established, in particular, in the design of planar and chip-based miniature device components for dense photonic integrated circuits. In many situations, the Bragg-grating structures are designed to function as a broad or narrow band-pass filter, as a multichannel coupled defects filter, an optical waveguide and an optical sensor. In this work, Bragg-grating concepts are applied in several different scenarios with applications ranging from Bragg-grating optical microcavity filter, Bragg-grating optical waveguide and a Bragg-slot waveguide. The Bragg-grating structures integrated with slot waveguide are shown to be very promising candidates for label-free optical sensing applications with sensitivity as high as 500nm/RIU. This work demonstrates the versatility of Bragg-grating structures for multiple device functionalities through design for a wide range of devices applications in several scientific and technological areas.

Advances in silicon photonics motivate the consideration of on-chip switch fabrics that combine switch elements into larger port-count switches. A major challenge is the large number of inter-stage waveguide crossovers. A novel freespace architecture utilising micro-lenses, capable of near zero insertion loss and crosstalk, is described and its principles of operation explained. The architecture is mapped to a planar implementation by the substitution of propagation in a slab-waveguide for free-space propagation and Luneburg lenses for the micro-lenses. Simulations show the careful approximation of the graded index of the Luneburg lens by a metamaterial introduces minimal additional crosstalk.

We review the properties of the generation of surface plasmons by subwavelength isolated slits in metal films and by small ensembles of slits. After an introduction, in Section 2, we recall the theoretical modal formalism that allows us to calculate the generation efficiency of SPP from the total field scattered by an indentation on a metal film. We also rapidly discuss the main results known of the SPP generation efficiency by subwavelength tiny slits or grooves. In Section 3, we consider the special case of wavelength-large slits that support two propagative modes and that allow us to dynamically control the direction of generated surface plasmons. In Section 4, we conclude by describing a compact and efficient device capable of launching SPPs in a single direction with a normally incident beam.

We focus on plasmonic modulators with a gain core to be implemented as active nanodevices in photonic integrated circuits. In particular, we analyze metal–semiconductor–metal (MSM) waveguides with InGaAsP-based active material layers. A MSM waveguide enables high field localization and therefore high modulation speed. The modulation is achieved by changing the gain of the core that results in different transmittance through the waveguide. Dependences on the waveguide core size and gain values of various active materials are studied. The effective propagation constants in the MSM waveguides are calculated numerically. We optimize the structure by considering thin metal layers. A thin single metal layer supports an asymmetric mode with a high propagation constant. Implementing such layers as the waveguide claddings allows to achieve several times higher effective indices than in the case of a waveguide with thick (>50 nm) metal layers. In turn, the high effective index leads to enhanced modulation speed. We show that a MSM waveguide with the electrical current control of the gain incorporates compactness and deep modulation along with a reasonable level of transmittance.

We address the experimental validation of the technological feasibility and operation of the metamaterials in a guided wave configuration in the spectral domain around 1.5μm. For our experiments we considered a 2D array of 200×50×50nm gold cut wires placed on the top of a 10μm wide and 200nm thick silicon waveguide. The transmission spectral measurements performed in the spectral range between 1.25 and 1.64μm using an end-fire coupling setup, revealed a marked dip for TE polarized light, corresponding to the cut wires resonance frequency obtained by numerical modeling. No such a dip in transmission was observed for TM polarized light, i.e. when the electric filed is perpendicular to the layers interface and the orientation of the cut wires. The scanning near field optical microscopy experiments (SNOM), performed in the same spectral range, revealed for TE polarized light a strong enhancement of the electric field confined in the region between the ends of the adjacent cut wires. These results confirm the efficient excitation of the cut wires resonance in a guided wave configuration for the TE polarization. The ability for local engineering of the field interaction with the metamaterial layer and thus the control in such a way of the light flow in a guiding slab, paves the way to a novel class of photonic devices.

Plasmonic slot waveguide (PSW) provides unique ability to confine the light in few nanometers only. It also allows for near perfect transmission through sharp bends. These features motivate utilizing the PSW in various on chip applications that require nanoscale manipulation of light. The main challenge of using these PSWs are the associated high losses that allow for propagation length of ~10 μm only. However, this constraint plays a minimal rule for circuits designed to have footprint in the order of few micrometers only. Thus, designing PSW with compact size and superior performance is of prime essential. Finite difference time domain (FDTD) is usually utilized for modeling of such networks. This technique is, however, inefficient as it requires very fine grid and carful manipulation of the boundary condition to avoid spurious reflections. In the paper, we present our recent equivalent circuit model that is capable of accurately modeling the various junctions including T and X shapes. This model is highly efficient and allows for obtaining a closed form expression of the response of any network of PSW with accuracy comparable to the FDTD results.

This work addresses a versatile modeling of complex photonic integrated circuits (PICs). We introduce a co-simulation solution for combining the efficient modeling capabilities of a circuit-level simulator, based on analytical models of PIC sub-elements and frequency-dependent scattering matrix (S-matrix) description, and an accurate electromagnetic field simulator that implements the finite element method (FEM) for solving photonic structures with complicated geometries. This is exemplified with the model of a coupled-resonator induced transparency (CRIT), where resonator elements are first modeled in the field simulator. Afterwards, the whole structure is created at a circuit level and statistical analysis of tolerances is investigated.

We show that the space-mapping algorithm, originally developed for microwave circuit optimization, can enable the efficient optimization of nanoplasmonic devices. Space-mapping utilizes a physics-based coarse model to approximate a fine model accurately describing a device. The main concept in the algorithm is to find a mapping that relates the fine and coarse model parameters. If such a mapping is established, we can then avoid using the direct optimization of the computationally expensive fine model to find the optimal solution. Instead, we perform optimization of the computationally efficient coarse model to find its optimal solution, and then use the mapping to find an estimate of the fine model optimal. In this paper, we demonstrate the use of the space mapping algorithm for the optimization of metal dielectric- metal plasmonic waveguide devices. In our case, the fine model is a full-wave finite-difference frequency domain (FDFD) simulation of the device, while the coarse model is based on the characteristic impedance and transmission line theory. We show that, if we simply use the coarse model to optimize the structure without space mapping, the response of the structure obtained substantially deviates from the target response. On the other hand, using space mapping we obtain structures which match very well the target response. In addition, full-wave FDFD simulations of only a few candidate structures are required before the optimal solution is reached. In comparison, a direct optimization using the fine FDFD model in combination with a genetic algorithm requires thousands of full-wave FDFD simulations to reach the same optimal.

In this paper, we propose a novel design-for-manufacture strategy for integrated photonics which specifically addresses the commonly encountered scenario in which probability distributions of the manufacturing variations are not available, however their bounds are known. The best design point for the device, in the presence of these uncertainties, can be found by applying robust optimization. This is performed by minimizing the maximum realizable value of the objective with respect to the uncertainty set so that an optimum is found whose performance is relatively immune to fabrication variations. Instead of applying robust optimization directly on a computationally expensive simulation model of the integrated photonic device, we construct a cheap surrogate model by uniformly sampling the simulated device at different values of the design variables and interpolating the resulting objective using a Kriging metamodel. By applying robust optimization on the constructed surrogate, the global robust optimum can be found at low computational cost. As an illustration of the method's general applicability, we apply the robust optimization approach on a 2x2 multimode interference (MMI) coupler. We robustly minimize the imbalance in the presence of uncertainties arising from variations in the fabricated design geometry. For this example device, we also study the influence of the number of sample points on the quality of the metamodel and on the robust optimization process.

The accuracy of the recently presented¹ equivalent step index approximation of multifilament core fibers is analyzed in terms of the effective refractive index, mode field area and bending losses of the fundamental mode. A modified Vparameter for this class of fibers as well as a single-mode condition is proposed. By comparison with a full-vectorial finite element method it is shown that the relative deviation of the effective refractive index and the mode field area are in the magnitude of 1 %. No significant decrease of bending losses is found for multifilament core fibers.

A new software tool and its application in the design of optical multiplexers/demultiplexers based on arrayed waveguide gratings is presented. The motivation for this work is the fact that when designing arrayed waveguide gratings a set of geometrical parameters must be first calculated. These parameters are the input for AWG layout that will be created and simulated using commercial photonic design tools. It is important to point out that these parameters influence strongly correct AWG demultiplexing properties and therefore have to be calculated very carefully. However, most of the commercial photonic design tools do not support this fundamental calculation. To be able to design any AWG, with any software tool and particularly to save the time needed for AWG design a new software tool was developed. The tool was already applied in various AWG designs and also technologically well-proven.

We present the results of the theoretical study and two-dimensional frequency domain finite-element simulation of tapered segmented waveguides. The application that we propose for this device is an adiabatically tapered and chirped PSW transmission, to eliminate higher order modes that can be propagated in a multimode semiconductor waveguide assuring mono mode propagation at 1.55μm. We demonstrate that by reducing the taper functions for the design of a segmented waveguide we can filter higher order modes at pump wavelength in WDM systems and at the same time low coupling losses between the continuous waveguide and the segmented waveguide. We obtained the cutoff wavelength as a function of the duty cycle of the segmented waveguide to show that we can, in fact, guide 1.55μm fundamental mode over a silicon-on-insulator platform using both, silica and SU-8 as substrate material. For the two-dimensional finite element analysis a new module over a commercial platform is proposed. Its contribution is the inclusion of the anisotropic perfectly matched layer that is more suitable for solving periodic segmented structures and other discontinuity problems.

This letter presents the theoretical investigation model to calculate the defect modes, modes loss of the slab, the group velocity of the defect region, and then calculate the normalized frequency of the defect region of Al_xGa_1-xAs at a wavelength of 1550 nm. A fast Fourier transform method was used to find the effect of varying refractive index on the modes frequency. This change of the refractive index enhancement is attributed to the transmission.

We introduce an ultra-sensitive integrated photonic sensor structure using silicon on insulator based triangular resonator, in which a surface plasmon resonance (SPR) gold film is applied on a total internal reflection mirror. We have analyzed and optimized the triangular resonator sensor structure with an extremely small SPR mirror sensing area. Due to the large phase shift in the SPR mirror, a significantly enhanced sensitivity of 800 nm/RIU (refractive index unit) and the maximum peak shift of half free spectral range have been obtained at the SPR angle of 22.65° with Au thickness of 35 nm for the change of the refractive index Δn = 1x10^-3.

Polarization controllers are demonstrated by integrated polymer waveguide technology. The integrated-optic polarization controllers consist of three birefringence modulators and 45°-inclined quarter-wave plates inserted between them. The birefringence modulator by incorporating highly birefringent polymer material exhibits the difference in phase retardation for TE and TM guided modes in proportion to the heating power. Thin-film quarter-wave plates are fabricated by using a reactive mesogen, and inserted between the birefringence modulators to produce static phase retardation and polarization coupling. By applying a triangular AC signal to one birefringence modulator and a DC signal to another, general polarization conversion covering the entire surface of the Poincaré sphere is demonstrated.

Flexible polymer waveguide with an imbedded Bragg grating is incorporated to form an external cavity lasers operating at near infrared wavelength. The third-order Bragg reflection grating imbedded in a polymer waveguide is optimized to produce an appropriate reflection spectrum for NIR-ECL with a center wavelength of 840 nm. Compressive strain and tensile strain were imposed across the flexible polymer device so as to achieve the wavelength tuning of 32 nm. The wavelength peak position was almost linearly proportional to the imposed strain, and the efficiency of wavelength tuning by the imposed strain was 0.9 pm/ μɛ.

An ideal diagnostic device should be inexpensive, easy-to-use, rapid and reliable. Nanostructured porous silicon (PSi) satisfies these criterions including label-free optical detection and high throughput detection. Pore morphology (size, porosity) must be tailored for each specific application, and for immunosensing applications PSi morphology has been optimized for maximal pore infiltration of larger proteins as immuno gamma globlulin (IgG). Sensor degradation by high salt concentration induces a baseline drift. Different thermal oxidation procedures have been studied in order to obtain a stable sensor in the 3 hour incubation period of the immunoassay with negligible drift

The purpose of this work is to analyze by simulation the coupling effects occurring in Arrayed Waveguide Grating (AWG) using the finite difference beam propagation method (FD-BPM). Conventional FD-BPM techniques do not immediately lend themselves to the analysis of large structures such as AWG. Cooper et al.¹ introduced a description of the coupling between the interface of arrayed waveguides and star couplers using the numerically-assisted coupled-mode theory. However, when the arrayed waveguides are spatially close, such that, there is strong coupling between them, and coupled-mode theory is not adequate. On the other hand, Payne² developed an exact eigenvalue equation for the super modes of a straight arrayed waveguide which involve a computational overhead. In this work, an integration of both methods is accomplished in order to describe the behavior of the propagation of light in guided curves. This new method is expected to reduce the necessary effort for simulation while also enabling the simulation of large and curved arrayed waveguides using a fully vectorial finite difference technique.