Wenrui Xue

Propagation Properties of a Modified Slot Surface Plasmonic Waveguide

In this paper, we present a modified slot surface plasmonic waveguide formed by metallic rod, core dielectric layer, and metallic film on the substrate. Using the finite-difference frequency-domain method, modal field distribution are analyzed firstly. Results show that the fundamental mode could be well confined in the space between the metal rod and the metal film. The dependence of modal field distribution, effective index, and propagation length of the fundamental plasmonic mode without gain on dielectric constant of the core layer, geometrical parameters, and working wavelengths are analyzed and discussed. A kind of available gain dielectric medium was used for the core dielectric layer to extend the propagation length. Results show that the propagation length can be extended observably with the help of the gain dielectric medium. Finally, effect of the thickness of the core dielectric layer on modal field distribution, effective index, and propagation length are analyzed and discussed. Since the modal field distribution, effective index, and propagation length can be controlled by adjusting the geometrical parameters, dielectric constant and gain of the core layer and working wavelengths of the waveguide, this kind of surface plasmonic waveguide can be applied to the field of photonic device integration and sensors.

Analysis of dispersion properties in hexagonal hollow fiber

A hollow fiber with new cross section is studied by means of a numerical simulator for modal analysis based on the finite-difference time-domain method (FDTD). Results show that light can be confined into the core area due to six right angles of the hexagonal glass with high index, and the peak intensity is located in the low-index air region. Distribution of the transverse electric-field intensity as well as dispersion properties of the fundamental mode are given.

Analysis of dispersion properties in square hollow fiber

A hollow fiber with new cross section was studied by means of a numerical simulator based on the finite-difference time-domain (FDTD) method. Its guiding mechanism was the right angle internal reflection. Results show that light can be confined into the air core due to the right angle guiding mechanism that was implemented with the hollow square glass. Distributions of the transverse electric field intensity as well as dispersion properties of the fundamental mode were given. This fiber can be used in optical communication, gas sensing, enhanced Raman scattering, CO/sub 2/ laser guidance, and particle transport.

Timing jitter in soliton transmission with super-Gaussian sliding-frequency filters

We derive an analytical expression for the variance of the timing jitter of a soliton transmission system using super-Gaussian sliding-frequency filters. By theory and computer simulation, we demonstrate that super-Gaussian sliding-frequency filters are more effective to reduce timing jitter than conventional filters without sacrificing the SNR. We also show that the sliding action of the super-Gaussian filters enhances timing jitter.

Direct method for the periodic amplification of a soliton in an optical fibre link with loss

A direct approach is applied to the periodic amplification of a soliton in an optical fibre link with loss. In a single soliton case, the adiabatic solution and first-order correction are given for the system. The apparent advantage of this direct approach is that it not only presents the slow evolution of soliton parameters, but also the perturbation-induced radiation, and can be easily used to investigate the system of dispersion management with periodically varying dispersion and other fields.

Research on the effects of air hole shape on the properties of microstructured optical fibers

We numerically analyze and compare the mode and disper- sion properties of three different microstructured optical fibers with the same square array of different-shaped air holes: rhombic, square, and circular. We use a full vectorial finite-difference method. The analysis shows that the properties of microstructured optical fibers depend on the hole area, hole shape, and wavelength to different extents. The effects of air hole shapes on the properties of microstructured optical fibers can be treated as the perturbations for sufficiently small air filling factors. For larger air filling factors the properties of microstructured optical fibers are clearly affected by the air hole shape. This dependence is useful for understanding the properties of microstructured optical fibers.

Stable propagation of solitons in strongly dispersion-managed unequal-length optical fiber link with loss

Using average approximation, we obtained a phase plane evolution picture of soliton propagated in strongly dispersion-managed optical fiber link with loss. After analyzed this picture, we proposed a new picture to keep soliton propagation stably in this system. Stable propagation parameters are given and twenty points we are interested in are selected. Using these parameters, we can construct any type of optical fiber link. Considering the length of article, we give two types of link with peak power 2 and 8 mW. With an input pulse train consisting of 32 bits in return-to-zero (RZ) format, numerical simulation has been done. We find that soliton can stably propagate through these optical fiber link constructed by ten unequal-length unit with a data rate of 13.33 Gb/s.

Control of soliton interactions by use of super-Gaussian sliding-frequency filters

We derived the theoretical results of soliton interactions in optical fiber with super-Gaussian sliding-frequency filters. The results demonstrate that the interactions between optical fiber solitons can be effectively suppressed by super-Gaussian sliding-frequency filters. And the results also show that the super-Gaussian filter with sliding is more effective in suppressing soliton interactions than that without sliding.

Short Hermite-Gaussian optical pulse propagation in dense dispersion-compensated systems

The transmission properties of Hermite-Gaussian optical pulses in fiber are studied. A theoretical solution is obtained by the momentum method, and the result is compared with a numerical simulation. Moreover, short Hermite-Gaussian optical pulse transmission over 1440 km in a dense dispersion-managed link is investigated on a numerical simulation basis. It is demonstrated that the pulse can propagate stably in zero, positive, and negative net dispersion compensation systems. In our simulation, both the second dispersion and the third-order dispersion are compensated. It is found that a Hermite-Gaussian optical pulse can transmit stably with reasonably lower power.

Quasi-soliton in optical fiber link with periodical dispersion management and power balance

Quasi-soliton exits in optical fibre link with periodical dispersion management and power balance. The analytical approximate expressions for the quasi-soliton are given. The evolution of the optical pulse width has the shape like a saw-tooth. The pulse width at the end of each unit cell is basically dependent on balance the average dispersion and nonlinear effect