This PDF file contains the front matter associated with SPIE Proceedings Volume 8198, including the Title Page, Copyright information, Table of Contents, Introduction, and Symposium committee listing.

We experimentally demonstrate two devices on the photonic crystal platform for chip-integrated optical absorption spectroscopy and chip-integrated biomolecular microarray assays. Infrared optical absorption spectroscopy and biomolecular assays based on conjugate-specific binding principles represent two dominant sensing mechanisms for a wide spectrum of applications in environmental pollution sensing in air and water, chem-bio agents and explosives detection for national security, microbial contamination sensing in food and beverages to name a few. The easy scalability of photonic crystal devices to any wavelength ensures that the sensing principles hold across a wide electromagnetic spectrum. Silicon, the workhorse of the electronics industry, is an ideal platform for the above optical sensing applications.

We demonstrate filtering characteristics of a polymer notch filter (PNF) with highly-ordered microphase-separated structure of block copolymers (BCPs). This PNF is characterized by an Optical Density > 5 blocking at the center wavelength and narrow blocking full bandwidth of 8 nm. Moreover, the wavelength is easily tuned by blending two BCPs with different molecular-weight. A low frequency Raman shift of 200 cm^-1 are, in fact, detected with a sufficient resolution by using this filter in Raman spectroscopy.

For the sake of clarifying the characteristics of cylindrical travelling wave and step index fiber, the modified zero order Hankel function, which is an approximate harmonic complex function without singularity, is recommended as the eigen function of cylindrical travelling wave in homogeneous dielectric. As the modified zero order Neumann function avoids the singularity in the origin of coordinate, and the concept of the essence of mode field of fiber is engaged, both of zero order Bessel function and modified zero order Neumann function are recommend as the eigen functions of axial electric or magnetic component in the core layer of step index fiber. Then, the analysing method of vector mode of fiber is used for reference, a new eigen equation of step index fiber is recommended. These may provide a new method for analyzing the characteristics of cylindrical travelling wave and step index fiber.

We report the impact of the pattern layout on the performance of Fano broadband reflectors based on 2D photonic crystals (PCs) on silicon-on-insulator. Two representative PC patterns including hexagonal and square are fairly compared with same buried oxide (BOX) layer thickness and equivalent refractive index of silicon layer by using 3D FDTD technique. Both red- and blue- spectral shifts are demonstrated with either addition of oxide on top, and/or selective etching of the BOX below. The hexagonal pattern can offer larger bandwidth with a bit lower reflectance as compared to square one. Additionally, it is more sensitive to etching thickness.

We present first-principles calculations of the band-gap properties of the zinc-blende BN, GaN and B_xGa_1-xN alloys. By 16-atom supercells to model a random alloy, the direct band-gap (Γ_15v-Γ_1c) bowing of 5.0 eV is obtained for B_xGa_1-xN alloys in the range of 0~37.5%, and the bowing parameter increases by 0.043eV/%B with boron (B) composition increasing. In addition, our calculated results show that 0.8eV (1550nm) direct transition band-gap energy of B_xGa_1-xN_yAs_1-y lattice matches to Si can be theoretically obtained while boron (B) composition is 4% and nitrogen (N) composition is 16%.

The technology of Polarization Optical Time Domain Reflectometer (POTDR) can be used to obtain the external events' information by measuring the change of state of polarization (SOP) of the Rayleigh backscattering in fiber. When the fiber is disturbed at two different positions simultaneously, we analyze the frequency spectrums of the change of Rayleigh backscattering light which are obtained by POTDR theoretically for ideal fiber, and by numerical simulation for single mode fibers. We find that the frequency spectrums between the first and second events contain the first vibration's frequency and its frequency multiplication. The frequency components of the spectrums after the second event are the linear combination of the first and the second events' frequencies. So we can obtain the location and the frequency information of the two events by analyzing the frequency spectrums. In addition, the frequency distribution in the frequency spectrums from different positions are different because of the different initial SOPs at different positions. So all the actual frequency information can not be obtained from only one frequency spectrum. We add up the frequency spectrums from the positions within a beat length to obtain the perturbation's frequency and the method can reduce the misdiagnosis rate because the sum of the frequency spectrums contains all the initial SOP within a beat length.

We present a numerical model for generating cylindrical vector beams (CVBs) through an ytterbium-doped few-mode fiber laser. A practical numerical model based on propagation rate equations with consideration of propagating modes competition between LP₀₁ and LP₁₁. To optimize the output power of LP₁₁ while depress LP₀₁, we analyze the dependence of this competition on resonant wavelength, pump power, ytterbium doped fiber (YDF) length, doping concentration and distribution. We also propose an effect method to completely depress the generation of LP₀₁.

In this paper, by utilizing two series connected Lyot-Sagnac filter, we propose a switchable erbium-doped fiber laser (EDFL) which can be switched between single-wavelength and multi-wavelength in the experiment. The laser can realize stable single-wavelength, dual-wavelength, triple-wavelength output at room temperature by adjusting polarization orientations of two polarization controllers(PCs) in the two series connected Lyot-Sagnac filter. The optical signal-to-noise ratio (OSNR) of the laser is over 30 dB, and the peak fluctuation over 30 minute is less than 0.5 dB at room temperature.

Based on the eigen equation and relationship among three normalized parameters, the approximate expression between the normalized standing parameter and the normalized frequency of TE₀₁ mode of step index fiber is recommended. Then, the characteristics of TE₀₁ mode field distribution is analyzed, the approximate expression between the radial coordinate for maximal amplitude of mode field and the normalized frequency is suggested. For the sake of clarifying the characteristics of diffraction far field of TE₀₁ mode of step index fiber, its expression is given according to the scalar diffraction integral formula. Then, the approximate expression between the normalized spatial frequency for the maximal spatial frequency spectrum and the normalized frequency is suggested. Numerical calculations show that the relative error between approximate value and exact value are small than one percent within a large variable range and this indicate that these approximate expressions are relatively reasonable.

A switchable dual-wavelength erbium-doped fiber laser is proposed. The proposed fiber laser, which utilizes a two-taper Mach-Zehnder interferometer filter as the wavelength-selective component, realizes single-, dual-wavelength switching by adjusting the curvature of two-taper. The side-mode suppression ratios (SMSRs) is over 36 dB and the power variation for each wavelength is less than 0.5dB in one hour under room temperature.

A novel tunable resonant cavity enhanced photodetector (RCE-PD) is achieved by using an air gap. The optical properties of the photodetector are designed by using the transfer matrix method (TMM). The quantum efficiency (QE) of the tunable RCE-PD is calculated and the optimizing structure is obtained. It is revealed that the peak QE increases to the highest value ( 92%) when the thickness of active layer is 106nm. When the air layer thickness changed 20nm under a low bias voltage, the peak wavelength blue shifts from 1550nm to 1547.9nm and the QE of the device keeps almost invariant at the same time.

We experimentally demonstrate an all-fiber similariton generation, amplification and compression laser system for the first time. The system can generate 4.1 nJ, 75.6-fs pedestal free pulses with 54 kW peak power. In addition, the pulse duration can be tuned through modifying the pump power. The corresponding spectrum width is 51 nm, and without spectral spikes. Such high quality ultra-short pulses are benefited from the linear chirp of similaritons. The seeded similariton is generated in a soliton-similariton switchable oscillator, in which, soliton or similariton can be chosen to emit alternatively by controlling polarization. Furthermore, we experimentally demonstrated the relationship between the gain and the spectral width of similaritons.

A novel all-optical encryption/decryption method based on stimulated Brillouin scattering (SBS) effect in optical fiber is proposed for the first time. The operation principle is explained in detail and the encryption and decryption performance is experimentally evaluated. The encryption keys could be the SBS gain amplitude, bandwidth, central wavelength and spectral shape, which are configurable and flexibly controlled by the users. We experimentally demonstrate the SBS encryption/decryption process of a 10.86-Gb/s non-return-to-zero (NRZ) data by using both phase-modulated and current-dithered Brillouin pumps for proof-of-concept. Unlike the traditional optical encryption methods of chaotic communications and optical code-division-multiplexing access (OCDMA), the SBS based encryption/decryption technique can directly upgrade the current optical communication system to a secure communication system without changing the terminal transceivers, which is completely compatible with the current optical communication systems.

A high-speed physical random number generator based on a chaotic laser was proposed and experimentally demonstrated. The broadband chaotic laser generated by an external cavity laser diode was employed as the physical entropy source. The chaotic signal was sampled and converted by an 1-bit analog-to-digital converter to a binary sequence with the rate of up to 1 Gb/s. To overcome the periodicity in random sequence due to the photo round trip time in the external cavity, the exclusive-or (XOR) operation on corresponding random bits in samples of the chaotic signal and its time-delay signal from a same single chaotic laser was executed. The scheme was simpler than the present random number generator in which random number sequences were obtained real-timely by doing XOR operation on the binary sequences from two chaotic semiconductor lasers. In addition, the proper selection of delay length was analyzed. A large number experiments show that when the corresponding delay time of autocorrelation trace with correlation coefficient of less than 0.007 is considered as the delay time between the chaotic signal and its time-delay signal, streams of random numbers can be generated with verified randomness.

We replace a commonly used Au film with an Au/Ag bimetallic film working as the sensing chip in the commercial surface plasmon resonance (SPR) instrument, Biacore 3000. The bimetallic chip gives out sharper SPR dip than that by the chip made of an Au film which can improve the sensitivity and accuracy. The applicability and stability of the bimetallic chip on the Biacore 3000 are tested by real-time monitoring of biological coupling processes between Sulfamethoxazole (SMX) and anti-SMX. The limit of detection of SMX is 1.8ng/ml.

The effect of the graded In_xGa_1-xAs layer on the distribution of the strain was studied by calculating the strain of different models using the finite element method. The results demonstrate that the graded In_xGa_1-xAs layer can reduce the strain and thus lead to longer emission wavelength. The results also demonstrate that the graded In_xGa_1-xAs layer can increase strain in the GaAs capping layer which cause disadvantage to grow stacked InAs/GaAs QD structure. But the strain can be released though increase the thickness of spacer layer when grow stacked structure.

The generation of space-variant polarized beams by segmented subwavelength metallic gratings is demonstrated theoretically and experimentally. First, the subwavelength metallic gratings acting as a polarizing beam splitters are designed and fabricated, and its transmission properties are measured. Next, the devices composed of space-variant subwavelength metallic gratings are proposed to convert incident circularly polarized beams into space-variant polarized beams. Several types of devices are fabricated by using of e-beam lithography (EBL) and reactive ion etching (RIE) technology. Finally, the intensity and polarization properties of generated beams are measured which show a good performance of high polarization purity.

A novel fiber laser configuration based on a polarization-maintaining fiber Sagnac loop mirror is proposed for generating linearly polarized light. The polarization-dependent reflectivity of the loop mirror provides the necessary polarization discrimination between the slow and fast axes. A robust linearly polarized all-fiber laser oscillator is demonstrated with a polarization extinction ratio better than 27 dB. After an integrated fiber amplifier, a 14.6 W narrow linewidth single-mode fiber laser at 1070 nm is obtained with an optical efficiency of 68% and a polarization extinction ratio of 22.4 dB.

The special optical fibers, with large mode field, are developed for fabricating high power optical fibers passive components. If a conventional fiber optical laser is used as optical source, the coupling efficiency between special optical fibers and conventional single mode fibers (SMFs) need to be improved. We investigate the specialty optical fibers property and its effect on the coupling efficiency using an electric arc fusion splicer. Improper splicing parameters can lead to coupling efficiency sharply decreased. Several splicing methods are utilized, and all the results are proposed. Comparing these results, we find a set of splicing parameters for reducing the scattering loss at the splice point. It was demonstrated that properly splicing parameters can make coupling efficiency greatly increased; furthermore, a balance between splicing strength and coupling loss was achieved.

We present a numerical investigation of nonlinear propagation of femtosecond pulses in photonic crystal fibers (PCFs) by solving the generalized nonlinear Schrodinger equation. The PCFs have a second-order dispersion of -48 ps²/km, nonlinear coefficient of 115 W^-1km^-1, and third-order dispersion (TOD) ranging from 0.1 ps³/km to 1 ps³/km at 1550-nm wavelength. The simulation results show that efficient spectral compression of ultrashort pulses can be induced in the regime of soliton self-frequency shift (SSFS) in PCFs when the input pulse parameters satisfy the condition 0.9 ≤N ≤ 1.2 for the soliton order N. It is found that the output spectral width is dependent on the peak power of input pulse and the PCF length. A spectral-compression factor up to 2.2 can be achieved for 50-fs, 1550-nm solitons propagating through 10-m PCF with a TOD of 0.5 ps³/km, where the soliton wavelength shifted from 1550 nm to 1698 nm. The effect of initial pulse chirp on output spectral width can be negligible for large PCF length. Greater spectral-compression factor can be obtained using PCF with larger TOD value. This SSFS-based spectral-compression scheme offers much promise for generation of narrow line-width tunable light sources in photonic applications.

The newly interfere and integrated fiber electro-optic intensity modulator was researched, it was made into Michelson interferometer by thermal poled hollow two-core fiber, and researched the modulation effect of the electro-optic intensity modulator. The result indicate that the poled fiber modulator have low half-wave voltage, and achieved a good effect on intensity modulate, it also realized electro-optic fiber modulator and Michelson interferometer integrated in one optical fiber. The electro-optic intensity modulator have good stability, simple structure and so on.

Direct laser driven ICF system requires a high degree of uniformity in laser energy in order to avoid Rayleigh-Taylor instability. In all-fiber laser driven ICF system, millions of fibers are fixed around the target chamber. We suggest the fibers are arranged in bundles with a single lens coupling the output of a bundle. If the arrangement is optimized, top-flat intensity profile is acquired near the focus of the lens. Least square method is used here in determining the optimum values of relative parameters. Factors on the irradiation nonuniformity are also analyzed here by numerical simulations.

A highly efficient TEM₀₀ mode 1063 nm Nd:GdVO₄ laser is accomplished with a simple plano-plano resonator. The laser threshold pump power is 856 mW. The maximum laser power of 2.05W is achieved when the pump power is 3.76 W, corresponding to a slope-efficiency of 70% to absorbed pump power. The quality of the output beam is analyzed with a laser beam quality analyzer. The perfect laser beam quality is partially attributed to the short cavity length of 11 mm and the precise temperature control to the Nd:GdVO₄ crystal. The output laser central wavelength is 1063.1 nm with a laser linewidth of 0.06 nm.

The effect of stimulated Brillouin scattering is considered and found to be important in high power optical fibers especially when amplifier is used. Numerical simulation has been done to show how the effect of stimulated Brillouin scattering is affects the amplified spontaneous emission and the signal. Found the difference between just decrease the Brillouin signal and decrease the NF, and give a method to decrease it through change the pump method.

The characteristics of dynamic gratings greatly affect the linewidth and mode hopping properties of ultra-narrow linewidth erbium-doped fiber lasers. In this paper, we propose a novel method to estimate the temporal evolution of the reflectance spectrum of the dynamic gratings recorded in EDF based on the transient effect of the erbium ions. An experimental setup is also proposed to measure the reflectivity spectrum of the dynamic gratings utilized in lasers. The experimental data are compared with the numerical results and their differences are analyzed. The experiment results reveal some important transient characteristics of dynamic gratings in real lasers which are helpful to understand the mechanism of mode hopping.

Stacking chirped pulse has been studied on its shape ability. When it propagates in single-mode fiber, the nonlinear effects become very significant because of high peak power. By numerical solving the nonlinear Schrodinger equation the simulation results indicate that stacking chirped pulse has different transmission characteristic from chirped pulse because of its special spectrogram distribution. In the paper, the dispersion length and the nonlinear length are modified for stacking chirped pulse. Even the SPM effects dominate over GVD effects in propagation, GVD effects should not be ignored or be treated as perturbation. More details about pulse evolution are discussed: as the stacking chirped pulse propagating, the pulse width changes little while the detail structure becomes unorganized and peak power decreases; the spectrum are significantly broadened because of the intense SPM effects.

Silica microspheres self-assembled on the outer surface of a standard single-mode silica optical fiber are investigated. The three dimensional colloidal crystals of FCC structure coating on the cylindrical substrate are fabricated through isothermal heating evaporation induced self-assembly. The resulting photonic crystal cylindrical annulus is characterized by scanning electron microscopy (SEM). The SEM images illustrate the [111] and [100]-oriented regions, besides the two zones regularly intercrossed pattern. Qualitative analysis and discussion are carried out for the arrangement of various oriented regions.

A prism coupled two-layer porous silicon waveguide beam splitter is presented. The component separates the input field into two orthogonally polarized beams. The splitter has been designed through beam propagation analysis by employing Finite-element method. Results obtained that the s and p polarization beams can be separated fully at a wavelength of 1.55μm.

Based on the technique of master oscillator power amplifier (MOPA), a two-stage ytterbium-doped fiber amplifier (YDFA) with all-fiber structure is theoretically simulated. The seed signal operating at the wavelength of 1064 nm has the characteristic of high repetition rate (10 MHz), ultrashort pulse duration (10 ps), low signal power input (20μW) and single longitudinal mode. The gain (and amplification stimulation emission power) is calculated at the different pump powers and gain fiber lengths of YDFA pumped by 975 nm. In addition, the amplifications at the different signal power inputs (1-25μW) are also simulated. The numerical results can be used to optimize the YDFA.