Optimal core diameter of terahertz (THz) pipe waveguide, when the bent condition is taken into account, is investigated. Numerical results show that the small bending radius the pipe waveguide suffers, the small optimal core diameter it will have. Moreover, the optimal core diameter increases slightly with the bending length.

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Guided mode resonance (GMR) enhanced near-infrared (near-IR)-to-visible upconversion fluorescence (UCF) from a rare-earth doped polymer resonant waveguide grating (RWG), comprised of a NaYF4:Yb/Tm nanocrystals doped poly-methyl-methacrylate (NaYF4:Yb/Tm-PMMA) thin layer. The intensity of the UCF can be enhanced compared with that from a flat area by matching either incoming near-IR excitation or out-going UCF extraction to the GMR wavelengths

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In this study, design, fabrication and characterization of the Si-based ARROW-B microring resonators for WDM applications were presented. The simulation results showed that the resonant wavelengths of these resonators were 1552.55 nm, 1556.74 nm, 1560.94 nm and 1565.13 nm, respectively. Compared with our measured drop wavelengths of 1553.35 nm, 1556.77 nm, 1559.31 nm and 1563.03 nm at through port, the deviations of resonant wavelengths were less than 0.1%.

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A single-longitudinal-mode selection is realised in a linear-cavity tunable fiber laser constructed using a Faraday rotator mirror and a fiber Bragg grating as the cavity ends. The measured optical signal-to-noise-ratio is larger than 40 dB with linewidth less than 1 MHz obtained using a saturable absorber asmode filter.

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We investigate the coupling behaviors of the slab type gain-guided index-antiguided (GGIAG) waveguides. It is found that the distance where one waveguide obtains maximum power and the distance where another waveguide has minimum power are different. The coupling length will be affected by the introduced gain in the core region.

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A bidirectional C+L band Erbium-doped fiber amplifier is proposed and demonstrated. Using 200 mW pump power at 1480 nm, the average gain is 15.4 dB and the average noise figure is 5.1 dB, respectively. The power penalty is less than 0.81 dB for a 75 km bidirectional transmission.

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1064 nm band Yb doped fiber laser is investigated using fiber Bragg grating as cavity end. High slope efficiency of 50% and low threshold power are obtained. The power variation is less than 0.1 dB in 13 nm tuning span. Single frequency lasing is realized with 2 dBm output power.

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We propose a highly birefringent structure operating at terahertz frequencies, which is composed of two identical subwavelength dielectric wires placed in parallel. Numerical simulations show that high birefringence can be achieved with a magnitude up to 0.0512.

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The modes on the metal strip plasmonic waveguide are analyzed using with the finite element method. The leaky mode has lower propagation loss than the bound mode. An etched-substrate structure is proposed to improve both the confinement of modal fields and the propagation length of the leaky mode.

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We design and simulate various One-dimensional photonic crystals on printed circuit board. In this report,we discuss the band structure, distribution of the electric field and slow light effect.

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We investigate the acousto-optic coupling in 1-D fishbone nanocavity with simultaneous photonic and phononic bandgaps. The strength of the acousto-optic interaction can be estimated by coupling rate calculation, based on both photo-elastic and moving-boundary effects. Both contributions can be in phase or out of phase in the total acousto-optic coupling.

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A high birefringence photonic crystal fiber with ultra-low confinement loss is proposed. An endlessly single mode, high birefringence 7.535×10-3, is found at the excitation wavelength at λ=1550 nm.

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The purpose of this research is combined with white light illumination and visible light communication on a LED array. A pre-equalization circuit used to improve the sign of communication, such as the back-end processing circuitry could allow the transport frequencies up to 1MHz.

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We numerically investigate the bending loss for index antiguided (IAG) fibers, in which the refractive index of the core is lower than that of the cladding. Numerical results show that, when the core diameter of the bent IAG fiber exceeds some critical value, the loss becomes core-independent.

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A novel inverse power splitter design is used by the 60 crossing as a fold plane. The 60-degree center-fold plane used by the self-image as the turning mirror is achieved to 2X2 60-degree multimode waveguide turning mirror coupler with inverse power splitter.

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We investigate the surface optical properties of a gold (Au) nanorod by using the finite-element method. We find that the near-field optical images show spatially oscillatory patterns on the surface of Au nanorod, and these phenomena are attributable to plasmon-mode wave functions.

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An improved gain-guided index-antiguided (GGIAG) fiber is proposed, in that a dielectric layer is introduced between the low-index core and the high-index cladding. Numerical results show that the pump is well-confined by antiresonant reflection, so that the end-pumping efficiency can be enhanced significantly.

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A compact waveguide polarization splitter in two-dimensional honeycomb photonic crystal is proposed. Both transverse electric and transverse magnetic wave are confined in the input waveguide. And the transverse electric wave is separated by the reflection effect, resulting in high polarization extinction ratio.

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An index sensor based on the cladding mode wavelength shift by using the tilted fiber Bragg grating (TFBG) is proposed to measure the liquid index variation and to observe the sensitivity effect in different cladding-thicknesses.

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