Shanliang Liu

Temporal characteristics of an optical soliton with distributed Raman amplification

The effects of distributed Raman amplification (DRA) on temporal characteristics of an optical soliton that are numerically investigated by using the split-step Fourier method are compared with the experimental data measured by employing the second-harmonic generation frequency-resolved optical gating analyzer. It is found that the numerical results are consistent with the experimental data. DRA that can compensate the fiber loss does not change the temporal wave form of the soliton. The soliton width performs a various oscillation with propagation distance when considering the fiber loss and different Raman gain. Compensation of the fiber loss increases with the increase of the Raman pumping power.

Photonic crystal fiber with two triangular arrays of semiminor-axis-decreasing elliptical air holes for single-polarization single-mode operation

A novel hexagonal lattice photonic crystal fiber (PCF) design with two triangular arrays of semiminor-axis-decreasing elliptical air holes is proposed in this paper. The PCF characteristics based on the full-vector finite element method with perfect matched layer boundary conditions show that a wider bandwidth and dispersion-flattened profile for single-polarization single-mode (SPSM) operation is achieved. The SPSM operation can be realized in a spectral region ranging from the wavelength of 1.4 to 2 μm. The profile with convex and dispersion-flattened dispersion is obtained from the wavelength of 1.391 to 1.624 μm.

Generation of a high-bit-rate optical millimeter wave

We propose a novel experimental system of optical millimeter wave with high-bit-rate. The system band is 40GHz, the high-bit-rate is 10 Gbps. The experimental results show that this is a good methodology to generate optical millimeter wave with efficient noise suppression and high-bit-rate.

A photonic crystal fiber for single-polarization single-mode operation

We propose a novel photonic crystal fiber (PCF) design for single-polarization single-mode (SPSM) operation. The proposed SPSM-PCF characteristics are investigated by using a full-vector finite element method (FEM) with perfect matched layer (PML) boundary conditions. The proposed SPSM-PCF performs SPSM operation for a wide range of wavelength. The results show that this is a good design methodology to realize broadband SPSM operation.

Propagation stability of a chirped soliton in birefringent fibers

The propagation stability of a chirped soliton at anomalous dispersion region in birefringent fibers is numerically studied by using the split-step Fourier-method. It is found that initial linear chirp can change obviously the threshold value Ath above which soliton stably propagates in birefringent fibers, the Ath increases with the decrease of the polarization angle | /4- |. The positive chirp makes obviously the Ath smaller for group velocity mismatch parameter >0.5, the negative one makes the Ath larger for <0.5. The effect of initial positive chirp on the Ath is greater than that of negative chirp for high birefringent fibers, is less than that of negative chirp for low birefringent fibers.

Effects of chirp and noises on autocorrelation characteristics of hyperbolic secant pulse

Effects of chirp and noises on autocorrelation characteristics of the linear chirped hyperbolic secant pulse are numerically investigated. It is found that the intensity autocorrelation curve and the pulse waveform are unchanged with the increase of the chirp parameter |C|. The spectral width and time-band product of autocorrelation spectral curve increase with the increase of |C|. The autocorrelation curves broaden near the center of the curves and heighten at the edges with the increase of the random noise, temporal window and sampling number. A method of filtering the random noise is given which is useful for us to use the SHG-FROG analyzer or the instruments based on autocorrelation technology.

Autocorrelation characteristics of the double-side exponential pulse with linear chirp

We numerically investigate the autocorrelation characteristics of the linear chirped double-side exponential pulse and their variations affected by the chirp and noise, compare with the relevant parameters of the exponential pulse, give a useful method of filtering the random noise.