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We proposed a new all-optical switch by using the phase modulation of spatial solitons. The proposed structure is composed of the nonlinear Mach-Zehnder interferometer (MZI) with the straight control waveguide, the uniform nonlinear medium and the nonlinear output waveguides. The local nonlinear MZI functions like a phase shifter. The light-induced index changes in the local nonlinear MZI make the output signal beam routing in the uniform nonlinear medium. The all-optical switching scheme employs angular deflection of spatial solitons controlled by phase modulation created in the local nonlinear MZI. By properly launching the control power and increasing the length of the uniform nonlinear medium, this device can be generalized to a 1xN all-optical switch. It would be a potential key component in the applications of ultra-high-speed optical communications and optical data processing system.

We propose a novel method for analyzing a multilayer optical waveguide structure with all nonlinear guiding films. This method can also be used to analyze a multibranch optical waveguide structure with all nonlinear guiding branches. The results show that agreement between theory and numerics is excellent.

The effects produced by different valency and amount of antimony ions on the resulting microstructures of ZnO varistors were studied. From the observation of scanning electron microscopy (SEM), the composition originally added with high valency of antimony ion had a larger grain size than that originally added with a low valency of antimony ion. Conversely, the composition originally added with a high valency of antimony ion possessed fewer intragrain particles than that originally added with a low valency of antimony ion. The spinel particle size and number of intragrain particles increased when the sintering temperature was raised. The compositions containing more antimony oxide can form more spinel phases, and result in an increase in grain growth kinetic exponent and activation energy as well as a decrease in grain size. These compositions have fewer intragrain particles and more spinel particles than those containing less antimony oxide.

This work demonstrated a new approach of planar multi-channel wavelength division multiplexing (WDM) system using photonic crystal structures. The system consists of a waveguide that is realized by a defect row of photonic crystal and high Q-value micro-cavities with asymmetric super-cell design. Two-Dimension (2-D) Finite-Difference-Time-Domain (FDTD) method is performed for simulation in this paper. The results showed good ability to filter an incident pulse into six spectral channels with a FHWM improved from 3.6 nm to 1.4 nm and the coherence length improved from 0.667 cm to 1.716 cm at the center wavelength 1550 nm channel and no transmission degradation. Six-channel coarse wavelength division multiplexing (CWDM) from 1490~1590 nm with channel spacing of 20 nm which defined by ITU-T Recommendation G.694.2 are presented. And the inter-channel cross-talk is smaller than -17 dB. The device design is leading the way to achieve CWDM specification and has good capability to extend the application of communication filed and fiber optical sensor field.