This PDF file contains the front matter associated with SPIE Proceedings Volume 7987, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

A drop and split filter (DSF) based on a self-collimation ring resonator (SCRR) in a hole-type photonic crystal is proposed and demonstrated. The DSF performance was investigated with the finite-difference time-domain (FDTD) simulation technique. By forming three splitters of the SCRR properly, self-collimation light can come out from two drop ports equally while no light come out from the through port. For the drop wavelength of 1550nm, the free spectral range is 29.7nm, which covers the whole optical communication C-band window. This DSF may have applications in photonic integrated circuits.

The optical and electrical variation green and blue silicon quantum dot (Si-QD) based MOSLED with the different thickness of SiO_x layer has been demonstrated. The turn-on voltage of the Si-QDs based MOSLED with the different RF plasma power is linearly enlarged by increasing the thickness of the SiO_x layer. The turn-on electric field is still constant at 6.6x10⁶ V/cm. The EL emission power of the blue Si-QD based MOSLED with increasing the thickness form 150 nm to 350 nm enhances from 55 nW to 470 nW due to the larger Si-QD amount from 1.5x10¹⁸ cm^-3 to 4.3x10¹⁸ cm^-3 in higher thickness. The blue Si-QDs based MOSLED with the SiO_x thickness of 350 nm has the maximum EL power of 470 nW. The EL wavelength of the blue Si-QD based MOSLED red-shifts from 420 nm to 450 nm when the SiO_x thickness increasing from 150 nm to 350 nm. The red-shifted phenomenon on EL spectra with increasing the thickness could be explained by means of the relationship between the varied Si-QD size and degraded electron conductivity. The EL wavelength of the Si-QD based MOSLED has a band filling effect phenomenon by the increment of the biased current and thickness. The distribution of Si-QD was uniform in whole SiO_x layer although there existed different Si-QD size.

A corrugation-pitch-modulated (CPM) distributed feedback (DFB) semiconductor laser based on reconstruction-equivalent-chirp (REC) technology is first experimentally demonstrated. The laser can suppress spatial hole burning (SHB) effectively and operates in good stable single longitudinal mode even the injection current very high.

Resonant coupling to radiation field in optical waveguides is simulated accurately and efficiently by complex coupled mode theory. Salient features of complex mode theory are demonstrated by investigation of transmission spectra in short/long period gratings.

Epitaxial Lateral Overgrowth has been proposed as a key technology of a novel hybrid integration platform for active silicon photonic components. By fabricating silicon oxide mask on top of a thin InP seed layer, we can use the so called defect necking effect to filter out the threading dislocations propagating from the seed layer. By optimizing the process, thin dislocation free InP layers have been successfully obtained on top of silicon wafer. The obtained characterization results show that the grown InP layer has very high quality, which can be used as the base for further process of active photonic components on top of silicon.

Chirp characteristics of silicon based Mach-Zehnder-interferometer (MZI) modulators with PIN diode and PN diode are fully analyzed, respectively. Simulation result shows that the chirp parameter is negative and influenced by the carrier absorption effect, the amplitude and frequency of applied sinusoidal modulating signals

Recent results on a new multiple-quantum-well saturable absorber (SA) device allowing fast responding power stabilization are reviewed. Combined with the classical SA achieving extinction ratio improvement, it allows all-optical amplitude-shift-keying 2R signal regeneration. Furthermore its phase-preserving characteristics make it potentially useful to prevent phase noise accumulation in phase encoded signals.

A novel photonic generation of power-efficient ultra-wideband (UWB) pulse by combining two asymmetric monocycle pulses with inverted polarities is experimentally demonstrated. The principle lies in cross-phase modulation (XPM) in a single semiconductor optical amplifier (SOA) and phase modulation to intensity modulation conversions in an arrayed-waveguide grating (AWG). The Federal Communications Committee (FCC) compliant UWB pulse gains 24.3 dB and 20.8 dB improvements compared to positive and negative monocycle pulses after power attenuation to respect the FCC spectral mask, respectively. The generated power-efficient UWB with pulse duration of about 310 ps has potential to achieve high speed transmission and modulation without overlapping and distortion.

We propose an ultra-broadband optical parametric amplifier (OPA) employing step-structure hybrid plasmonic waveguide with ultra-high nonlinearity. The proposed parametric amplifier possesses a net signal gain of larger than 14 dB and a 3-dB bandwidth of over 200 nm covering C-band, L-band, and S-band.

We experimentally demonstrate an efficient coupler between a silicon waveguide and a hybrid plasmonic waveguide for the wavelength range 1460-1540 nm. The coupling efficiency for a single coupler is ~70% in the whole spectrum range which is consisted with the theoretical prediction. Such compact, efficient plasmonic couplers provide a promising platform for integrated photonic circuits.

The strain field and elastic energy due to interfacial misfit dislocation networks near the free surface have been calculated analytically. The result predicted the preferential nucleation sites of self-assembled quantum dots with the influence of dislocation networks. Compared with Green function method, our solution is simple, direct and can solve the problem completely.

A semiconductor QD fiber amplifier (SQDFA) is proposed and theoretically researched. The fiber amplifier makes use of a tapered twin SMF coupler and a PbS QD-film is coated on the surface of it. In the tapered region, QDs will be excited by the evanescent wave of a pump and produce a gain on signal. The fiber coupler is properly designed to ensure a desired power ratio of the output signal. Using a 1530-nm signal and a 980-nm pump, an optical gain of about 8 dB is achieved with a gain efficiency of 3.48dB/cm. This SQDFA has unique advantages including suppression to the amplified spontaneous emission (ASE), simple fabrication and lower insertion loss and thus has a great potential in fiber communication systems.

It has been observed experimentally that the band edge photoluminescence of GaInNAs Quantum well (QW) materials is broadened resulting from band-tailing, localised states or conduction band edge fluctuations. In this paper we develop a model for N compositional fluctuations causing conduction band edge fluctuations which localise the electrons into the resulting quantum dots (QDs). The electron dynamics in the QDs and QW states are examined using a rate equation approach and the carrier populations presented as a function of barrier height and temperature. This mechanism could lead to broad gain in GaInAsN QW structures which could be useful for broad band SOAs for optical communications.

Thermal conductivity in GaN/AlGaN heterostructures is investigated by solving the steady-state phonon Boltzman equation in the relaxation-time approximation using phonon density of state, average group velocity and phonon relaxation time. In this paper dispersion curves, group velocity, density of states of energy, relaxation time of phonon and finally thermal conduction of several types of symmetric and asymmetric nanostructures are simulated. It has been concluded that proper selection of layer widths yields minimum thermal conduction in the considered structure. Also, making the structure asymmetric, affects the thermal conduction.

We demonstrated AlGaN-based multi-quantum-well (MQW) deep-ultraviolet (UV) light-emitting diodes (LEDs) with wavelengths in the range of 222-351 nm, fabricated on low threading dislocation density (TDD) AlN template on sapphire. High internal quantum efficiency (IQE) of 50-80% was observed from AlGaN or quaternary InAlGaN MQWs by fabricating them on low TDD AlN templates. Also, an electron injection efficiency (EIE) was markedly improved by using multi-quantum barrier (MQB). Over 20 mW cw output power was obtained for 256-275 nm LEDs, which will be useful for sterilization applications. The maximum external quantum efficiencies (EQEs) were 1.8 and 2.75% for 247 and 270 nm AlGaN-LEDs, respectively.

Injectorless quantum cascade lasers are lately getting more and more into focus of research, as they promise lower threshold current densities and higher output powers and efficiencies. Although the research on them started seven years later in 2001 and was less intensive, they have achieved much lower threshold current densities with 0.45 kA/cm² at 300 K compared to injectorbased devices. Additionally injectorless devices reached efficiencies and output powers in the important wavelength range between 8 and 12 μm comparable to best performing injectorbased devices. With 2 W per facet and an overall efficiency of 7 % around 9 μm, they show a strong potential regarding possible applications.

This paper will introduce the fabrication methods of electro-absorption modulated lasers (EMLs) and the latest results of EMLs fabricated by a novel technology named selective area growth double-stack active layer (SAG-DSAL) developed by the authors.

More than 11mW output powers for all wavelengths from the fiber and over 49 nm range tuning in sampled grating distributed Bragg reflector laser with an integrated semiconductor optical amplifier which is enabling access to 110 ITU 50GHz channels is demonstrated. Tilted amplifier and anti-reflection facet coating are used to suppress reflection.

Fast wavelength-tunable semiconductor lasers will be the key components in future optical packet switching networks. Especially, they are of great importance in the optical network nodes: transmitters, optical wavelength-routers, etc. In this paper, a new scheme of a next-generation fast tunable ring laser was given. Tunable lasers in this design have better wavelength tunability compared with others, for they are switched faster in wavelength and simpler to control with the injecting light from an external distributed Bragg-reflector(DBR). Then some discussion of the waveguide material system and coupler design of the ring laser were given. And we also derived the multimode rate equations corresponding to this scheme by analyzing some characteristics of the semiconductor ring cavity, directionality, nonlinear mode competition, optical injection locking, etc. We did MatLab simulation based on the new rate equations to research the process of mode competition and wavelength switching in the laser, and achieved the basic functions of a tunable laser. Finally some discussion of the impact of several key parameters was given.

A tunable and switchable single-longitudinal-mode (SLM) dual-wavelength fiber laser incorporating a reconfigurable dual-pass Mach-Zehnder interferometer (MZI) filter and its application in microwave generation was proposed and demonstrated. By incorporating a dual-pass MZI into an erbium-doped fiber ring cavity, tunable and switchable SLM dual-wavelength operation can be conveniently realized.

N-doped GaAs nanowires (NWs) were grown on GaAs (111) B substrate by means of vapor-liquid-solid (VLS) mechanism in a metalorganic chemical vapor deposition (MOCVD) system. Two flux rates of n-type dopants used for GaAs NWs growth were researched. For comparison, undoped GaAs NWs were grown at the same conditions. It is found that all NWs are vertical to the substrate and no lateral growth occurs. The growth rate is proportional the flux rates of n dopant. It is observed that there is Gibbs-Thomson effect in doped NWs. Pure zinc blende structures without any stacking faults from bottom to top for all three samples were achieved.

Self-assembled lateral aligned InAs quantum dot molecules (QDMs) with In_xGa_1-xAs strain-reducing layer are grown on GaAs substrate by metal-organic chemical vapor deposition. The effects of growth temperature and In content of In_xGa_1-xAs on the structural and optical properties of QDMs are investigated by using atomic force microscopy and photoluminescence. It is found that through appropriately selecting growth parameters, QDMs composed of two closely spaced InAs QDs are formed, and a redshift of emission wavelength and wideband photoluminescence spectra of QDMs are observed, which make QDM a potential candidate for broadband optical devices.

A method to reconstruct a chirped quasi-phase-matching grating by using a discrete layer-peeling algorithm is demonstrated. The coupling distribution and grating structure can be synthesized from the transmission spectrum. Experimental verification shows that the method can reconstruct the grating distribution efficiently. This method can be used an efficient approach of quality inspection on quasi-phase-matching grating.

An all-optical UWB pulses generation and modulation scheme based on a semiconductor optical amplifier and a DWDM is proposed and demonstrated, which has potential applications in multiuser UWB-Over-Fiber communications systems. Using proposed scheme, pulse amplitude modulation (PAM), pulse polarity modulation (PPM) and pulse shape modulation (PSM) can be conveniently realized.

The microring resonator is a high-performance and low-cost optical waveguide device, suitable for integration with large dimensions. This paper presents the design of laterally coupled racetrack microring resonators working around 1.55μm, using combinations of the 3D full vectorial film mode matching method, the coupled mode theory and the parameter model. This combined simulation technique shows convenience to perform the design process.

We numerically calculate the switching performance of all-optical ultra-fast gate switches employing the cascade of second harmonic generation and difference frequency mixing in periodically poled lithium niobate devices. In the analyses, the device fabrication errors are considered. We show that the domain length error decreases the switching efficiency significantly.

We propose a cascaded quasi-phase matched (QPM) lithium niobate (LN) device. In the device, two QPM-LN crystals with different domain inversion periods are cascaded. We numerically show that the cascaded QPM-LN device has an all-optical decision gate function, thus enabling a compact and stable 3R circuit.

Raman scattering enhancement characteristic of a new kind of Nb-doped silica fiber has been studied in this paper. This Nb-doped special silica optical fiber is fabricated on Modified Chemical Vapor Deposition (MCVD) (which is the traditional fiber preform fabrication technologies) combined with Atomic Layer Deposition (ALD). Meanwhile, Raman spectrum of different length Nb-doped special silica optical fiber samples has been measured with the 785nm exciting light. Then, it develops the measurement comparison between Nb-doped special silica optical fiber and conventional single-mode optical fiber in the wavelength range from 820nm to 920nm. The measuring results indicate that the new Nb-doped special silica optical fiber shows higher Raman scattering intensity compared with conventional single-mode optical fiber. On the other hand, the inferred spectrum of the new Nb-doped special silica optical fiber is also measured, and its measurement wavenumber range is from 400 cm^-1 to 4000 cm^-1. Finally, the loss spectrum of the Nb-doped special silica optical fiber is measured and its loss at 1550nm is 0.01dB/m.

An all-passive dual polarization optical 90°-hybrid in silicon-on-insulator waveguides is proposed and designed. It consists of two 2x2 MMI-MZI structures, working as polarization beam splitters, and two 4x4 MMI couplers, working as 90°-hybrids. The fabrication process includes only one step of inductively coupled plasma (ICP) etching. It is particularly suitable for silicon-based integration of DP-QPSK receiver.

A high-speed programmable semiconductor pulse seed laser, with maximum 20A peak current, and 10Hz-1MHz continuously adjustable repetition frequency, 16ns-1μs continuously adjustable pulse width was designed for MOPA pulsed fiber laser. The experiment results show that this programmable semiconductor pulse seed laser works stably.

The three-wave conversions (such as the nonlinear generation of light pulses of second harmonic frequency and parametric amplification of light signals), photo-induced in all-optically polled glasses materials, have been investigated. Theoretical considerations of the investigated phenomena show the interesting peculiarities of the process of three-wave conversions in photo-integrated volumetric micro-structures of nonlinear polarizability with the existence of a regime of synchronous two-beam transformations of light pulses. During the experimental investigation of the phenomena in the bulk oxide glasses the complicated kinetics of the formation of second-order polarizability gratings has been detected. Some properties of the phenomena have been studied and the possible mechanisms of the dynamics of processes are discussed.

In this study, for increasing absorption of the active layer in bulk heterojunction (BHJ) organic solar cells (OSCs), we used surface Plasmon effect. For showing the results, we investigated the proposed structure with Finite Difference Time Domain (FDTD) numerical method and achieved electromagnetic field characters. It is shown that the proposed structure enhance the absorption coefficient as well as bandwidth.

The CdSe quantum dots have been synthesized and their optical properties have been investigated at 775 nm. It was found that both linear absorption and linear scattering were negligible in these colloidal cadmium selenide quantum dots when the light intensity was weak. A strong light-induced scattering was observed when a strong 150 fs Ti:Sapphire laser incident on the sample. The physical origins and the possible photonic applications of this phenomenon were investigated.

we propose the improved dual-wavelengthpumped scheme based on the former work (C.Xiong et al, Journal of lightwave tech. 27, 1638-1643(2009)), which can obviously increase the power at the visible wavelengths and effectively improve the flatness of spectra by solving the Generalized Nonlinear Schrödinger Equation with the adaptive split-step Fourier method and simulating supercontinuum generation.