This PDF file contains the front matter associated with SPIE Proceedings Volume 10622, including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

Polymer nanofibers are cheap and flexible building blocks for nanophotonic components. For high density nanophotonic integration, both passive and active polymer nanofibers are desirable. In contrast to passive polymer nanofibers, active polymer nanofibers are more desirable because they can act as a light source and waveguide simultaneously. In this talk, light emission in quantum dots and dyes doped polymer nanofibers will be introduced.

Silicon-based optical microcavities are very popular for many applications because of the ultra-compact footprint, easy scalability, and functional versatility. In this paper we give a discussion about the challenges of the optical microcavities on silicon and also give a review of our recent work, including the following parts. First, a near-“perfect” high-order MRR optical filter with a box-like filtering response is realized by introducing bent directional couplers to have sufficient coupling between the access waveguide and the microrings. Second, an efficient thermally-tunable MRR-based optical filter with graphene transparent nano-heater is realized by introducing transparent graphene nanoheaters. Thirdly, a polarization-selective microring-based optical filter is realized to work with resonances for only one of TE and TM polarizations for the first time. Finally, a on-chip reconfigurable optical add-drop multiplexer for hybrid mode- /wavelength-division-multiplexing systems is realized for the first time by monolithically integrating a mode demultiplexer, four MRR optical switches, and a mode multiplexer.

Frequency comb generation in the mid-infrared (mid-IR)region is attractive recently. Here, we propose the Ge-on-Si microresonator for power-efficient frequency comb generation in the mid-IR. An octave-spanning comb can be obtained with power reduced to 190 mW. The robustness of the frequency comb generation with localized spectral loss is also analyzed. Based on the analysis, we propose a novel architecture of on-chip spectroscopy systems in the mid-IR.

Mechanism of the two-port one input mirror-symmetric all-dielectric disk array perfect absorbers is studied by temporal coupled mode theory. The perfect absorption is resulted from the degenerate critical coupling of EH¹¹¹ and HE₁₁₁ modes of the dielectric disks. Analytical absorption with parameters extracted from Eigen-frequency analysis matches well with that by Scattering parameter simulations, we also show that the asymmetric total field is due to the different symmetry of the two modes. The effect of the geometric parameters and material loss tangent is also investigated, which can guide the design of such all-dielectric perfect absorbers.

Molybdenum disulfide (MoS₂) monolayer, a two dimensional (2D) layered transition metal dichalcogenides with its novel nanoelectronic and optoelectronic properties has been investigated and applied widely. MoS₂-based hybrid composites have shown great potential in chemical and biological fields by combining the advantages of several structures. In our work, a SERS-active substrate was fabricated by combining the MoS₂ monolayer with Ag Nanowire (NW)−Nanoparticle (NP) structures using a spin-coated method. This AgNW−AgNP−MoS₂ hybrid structure was characterized by SEM, UV-Vis and Raman spectroscopy. Experimental results indicate that strong SERS signals of rhodamine 6G (R6G) molecules is able to be achieved at the “hotspot” formed in this hybrid structure. The enhancement factor is high up to 10⁶ as the incident laser is polarized perpendicular to the NW and the limit of detection is found to be as low as 10^-11 M. Besides, the fabricated SERS substrate was reliable and reproducible, which showed great potential to be an excellent SERS substrate for chemical and biological detection.

ZnO has attracted much attention because of its high-energy gap and exciton binding energy at room temperature. Compared to ZnO thin films, ZnGaO thin films are more resistive to oxidation and have smaller deformation of lattice. In this study, the high purity ZnSe and Ga₂O₃ powders were weighted at a molar ratio of 18:1. Se was oxidized to Se₂O₃ and separated from the mixture powders by using conventional solid state reaction method in air, and the ZnGaO ceramic target was prepared. We fabricated the ZnGaO films on silica glass by pulsed laser deposition (PLD) method under different oxygen pressure at room temperature. The as-grown films were tested by X-ray diffraction and atomic force microscope (AFM) to diagnose the crystal structure and surface morphology. Moreover, we obtained the optical transmittance of ZnGaO film and found that the electrical conductivity capacity varied with the increase of oxygen pressure.

In this letter, we theoretically investigate the impact of the incident light polarization on photonic spin splitting induced by the photonic spin Hall effect when a linearly polarized Gaussian beam is reflected from an air-glass interface around the Brewster angle. We calculate the spin splitting shift as a function of the incident light polarization under different incident angles. We find that a tiny variation of the incident light polarization can result in a dramatic change of the spin splitting shift, and the highest sensitivity is up to 6.8 μm/deg . The largest splitting shift can reach 5.3 μm, which is larger than the previously reported values. We also find that the direction of spin accumulation of photons with different spin directions can be switched by adjusting the incident angle around the Brewster angle when the incident light polarization is near the p-polarization. These findings may be useful for precise polarization metrology and photon modulation.

In this study Electronic states and optical properties of self assembled InAs quantum dots embedded in GaAs matrix have been investigated. Their carrier confinement energies for single quantum dot are calculated by time-independent Schrödinger equation in which hamiltonianian of the system is based on effective mass approximation and position dependent electron momentum. Transition energy, absorption coefficient, refractive index and high frequency dielectric constant for spherical, cylindrical and conical quantum dots with different sizes in different dimensions are calculated. Comparative studies have revealed that size and shape greatly affect the electronic transition energies and absorption coefficient. Peaks of absorption coefficients have been found to be highly shape dependent.

Quantum Dots (QDs) intermediate band solar cells (IBSC) are the most attractive candidates for the next generation of photovoltaic applications. In this paper, theoretical model of InAs/GaAs device has been proposed, where we have calculated the effect of variation in the thickness of intrinsic and IB layer on the efficiency of the solar cell using detailed balance theory. IB energies has been optimized for different IB layers thickness. Maximum efficiency 46.6% is calculated for IB material under maximum optical concentration.

The capability to detect optical signals over a broad wavelength band is highly important for practical device applications. However, high speed responsive across entire wavelength band within a single photodetector remains challenge. Here we demonstrated a broadband photodetector using a single quantum-dot-doped polyaniline nanowire with a broadband responsive at 350-700 nm (see schematic). The high responsivity is attributed to the high density of trapping states at the enormous interfaces formed in polyaniline and quantum dots. The interface trapping can effectively reduce the recombination rate, promote the separation of photogenerated carriers, and then enhance the efficiency for optical detection.

Micro channel Plate (MCP) is a kind of large-area array electron multiplier with high two-dimensional spatial resolution, used as high-performance night vision intensifier. The high precision control of the fiber is the key technology of the micro channel plate manufacturing process, and it was achieved by the control of optical fiber drawing machine driven by dual-motor in this paper. First of all, utilizing STM32 chip, the servo motor drive and control circuit was designed to realize the dual motor synchronization；Secondly, neural network PID control algorithm was designed for controlling the fiber diameter fabricated in high precision; Finally, the hexagonal fiber was manufactured by this system and it shows that multifilament diameter accuracy of the fiber is ± 1.5μm.

In this paper, a method that adds an inverse taper at the endface of the waveguide is analyzed to reduce the silicon waveguide endface reflection (SWER). A high index-contrast optical waveguide on a silicon-on-insulator (SOI) wafer allows for the strong optical confinement, while it also brings in a substantial endface reflection. Most parameters of the taper, such as the length and tip width of the taper, and wavelength of the guided light, even the shape of the taper, have been studied in detail using the three-dimensional finite-difference time-domain (3D-FDTD) method to reduce the SWER. In addition, we have also proposed a new structure that adds the special taper to the straight-through port of the 3-dB directional coupler (DC) to measure the SWER in experiments. The experimental results show good agreement with our simulation results. This taper is useful and small enough that can be applied to many silicon photonic devices and large scale photonic integration circuits (PICs).

Infrared detecting and display device（IR-DDD）is a newly developed optical up-conversion device that integrates the light-emitting diode（LED）onto the infrared （ IR ） photo-detector, in order to convert IR light into the carriers photo-generated in detection materials and inject them into LED to emit visible light. This IR-DDD can achieve the direct up-conversion from IR ray to visible light, showing the considerable potential in night-vision application. This paper attempts a review of its working principle and current research progresses.

In this work, we design and fabricate a highly compact third-order racetrack add-drop filter consisting of silicon waveguides with modified widths on a silicon-on-insulator (SOI) wafer. Compared to the previous approach that requires an exceedingly narrow coupling gap less than 100nm, we propose a new approach that enlarges the minimum feature size of the whole device to be 300 nm to reduce the process requirement. The three-dimensional finite-difference time-domain (3D-FDTD) method is used for simulation. Experiment results show good agreement with simulation results in property. In the experiment, the filter shows a nearly box-like channel dropping response, which has a large flat 3-dB bandwidth (~3 nm), relatively large FSR (~13.3 nm) and out-of-band rejection larger than 14 dB at the drop port with a footprint of 0.0006 mm² . The device is small and simple enough to have a wide range of applications in large scale on-chip photonic integration circuits.

As the numerical aperture (NA) of the projection objective increases continually and the exposure pattern feature size decreases gradually, the polarization illumination is introduced into the lithography system. Therefore, it is necessary to design a wide field-of-view (FOV) wave plate to eliminate the effect of oblique incident light on the phase delay of the traditional zero order wave plate effectively. The quarter-wave plate with 20° FOV based on birefringent optical crystals has been designed in our laboratory by Dong et al. In order to obtain a wider FOV, we explore a previously reported Ag patch ultrathin quarter-wave plate whose performances were not analyzed by finite-difference time-domain (FDTD) method. In this paper, we mainly investigate three performances of the Ag patch quarter-wave plate consisting of FOV, achromatic band and achromatic band transmission. The simulation results indicate that when phase difference error is controlled at ±2° (1) the range of FOV of the quarter-wave plate is ±29° at 632nm; (2) the achromatic band ranges from 618nm to 658nm at normal incidence; (3) the achromatic band transmission ranges from 11% to 30%. Compared with the traditional wave plate made of birefringent crystals, the achromatic band and transmission is slightly lower but the FOV of this quarter-wave plate is much wider. Thus, this Ag patch nanoscale wide FOV quarter-wave plate can be effectively used in high NA lithography projection exposure systems to reduce the polarization aberration caused by oblique incidence of light.

Reconstruction equivalent chirp (REC) technique is widely used in the design and fabrication of semiconductor laser arrays and tunable lasers with low cost and high wavelength accuracy. Bent waveguide is a promising method to suppress the zeroth order resonance, which is an intrinsic problem in REC technique. However, it may introduce basic grating chirp and deteriorate the single longitudinal mode (SLM) property of the laser. A nonlinear equivalent chirp pattern is proposed in this paper to compensate the grating chirp and improve the SLM property. It will benefit the realization of low-cost Distributed feedback (DFB) semiconductor laser arrays with accurate lasing wavelength.

The high diffraction efficiency and high dispersion ability of diffraction grating plays a very important role in laser systems. Fused-silica transmission gratings not only have board band, high diffraction efficiency and high damage threshold, but also have the advantage of light path without shelter comparing to reflective gratings. In this paper, the study of polarization-independent transmission fused-silica grating is carried out, and the influence of rectangular and trapezoidal grating microstructures on the -1st diffraction efficiency of grating is analyzed. For trapezoidal groove structure, in the range of 80 to 90 degrees, the distributions of diffraction efficiency at different bottom angle are calculated and analyzed. The structure parameters of the grating are optimized by rigorous coupled wave theory. The designed grating groove density is 1440 lines/mm. The -1st diffraction efficiency of the grating is over 96% for both of TE and TM polarized waves at the Littrow angle (49.7 degrees) with the center wavelength of 1060nm. Within the bandwidth of 42nm (from 1039 to 1081nm), the -1st diffraction efficiency of the designed grating is theoretically greater than 90% for both of TE and TM polarized waves.

SU-8 optical waveguides and devices are developed for the 2 μm wavelength range for the potential applications in the future high-capacity optical communications operating at 2 μm. The mode properties of the SU-8 optical waveguides are analyzed numerically. The SU-8 optical waveguides and devices are fabricated with the spin-coating process. The measured propagation losses for the fabricated SU-8 optical waveguides is about 10dB/cm. The demonstrated microring resonator (MRR) has a Q-value of 5000.

Based on the metamaterial composed of symmetrical split resonant ring, a broadband reflective terahertz polarization converter is proposed. The numerical simulation shows that it can rotate the polarization direction of linear polarized wave 90° in the range of 0.7-1.8THz and the polarization conversion ratio is over 90%. The reflection coefficient of the two electric field components in the diagonal direction is the same and the phase difference is 180° ,which leads to the cross-polarization rotation.In order to further study the physical mechanism of high polarization conversion, we analyze the surface current distribution of the resonant ring. The polarization converter has potential applications in terahertz wave plate and metamaterial antenna design.

Recently, due to its superior characteristics and simple manufacture, such as small size, low loss, high sensitivity and convenience to couple, the optical fiber sensor has become one of the most promising sensors. In order to achieve the most effective realization of light propagation by changing the structure of sensors, FOM(S •Q/λ_res) ,which is determined by two significant variables Q-factor and sensitivity, as a trade-off parameter should be optimized to a high value. In typical sensors, a high Q can be achieved by confining the optical field in the high refractive index dielectric region to make an interaction between analytes and evanescent field of the resonant mode. However, the ignored sensitivity is relatively low with a high Q achieved, which means that the resonant wavelength shift changes non-obviously when the refractive index increases. Meanwhile, the sensitivity also leads to a less desirable FOM. Therefore, a gradient structure, which can enhance the performance of sensors by achieving high Q and high sensitivity, has been developed by Kim et al. later. Here, by introducing parabolic-tapered structure, the light field localized overlaps strongly and sufficiently with analytes. And based on a one-dimensional photonic-crystal nanofiber air-mode cavity, a creative optical fiber sensor is proposed by combining good stability and transmission characteristics of fiber and strengths of tapered structure, realizing excellent FOM ~4.7 x 10⁵ with high Q-factors (Q~10⁶) and high sensitivities (<700 nm/RIU).

We have proposed and realized nonreciprocal light propagation by a structure consisting of graphene photonic crystal and magneto-optical semiconductor. The nonreciprocal transmission is caused by magnetic Tamm plasmon polaritons which exit on the interface of graphene photonic crystal and magneto-optical material. Transmission spectrum is investigated to analyze the influence of structural parameters, external magnetic field, and graphene chemical potential on magnetic Tamm plasmon polaritons. We show that it is possible to realize active control on unidirectional light by altering external magnetic field and graphene chemical potential. And one-way transmission can be easily switched from forward to backward propagation.