Article

All-optical differentiator and high-speed pulse generation based on cross-polarization modulation in a semiconductor optical amplifier.

Institute of Optical Information and Key Laboratory of Luminescence and Optical Information of Ministry of Education, Beijing Jiaotong University, Beijing, China.
Optics Letters (Impact Factor: 3.18). 04/2009; 34(6):830-2. DOI: 10.1364/OL.34.000830
Source: PubMed

ABSTRACT We propose an all-optical intensity differentiation scheme based on cross-polarization modulation (XPolM) in a semiconductor optical amplifier (SOA) while demonstrating the absolute value of differential signal that can be obtained by the SOA-based XPolM of two parts with relative delay from the input signal and well extracted by the polarization filter. The differentiation errors and eye diagrams versus sampling time Delta are investigated for data rate at 12.5 Gbits/s, and the minimal error approximately 0.06 is achieved at Delta=0. Owing to a much faster polarization response, our scheme bears great potential for all-optical signal processing over 100 Gbits/s. By application of the differentiator, we further obtain the 20 GHz short pulse train with a pulse width of approximately 10 ps.

0 Bookmarks
 · 
73 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, a method for generating ultra-short optical pulses in the sub-picosecond regime is presented and numerically demonstrated using a nonlinear nanoporous silicon waveguide followed by a Mach-Zehnder interferometer configuration based on the GaInP photonic crystal waveguide. Research results show that an optimal output pulse with sub-picosecond time duration can be achieved from ~16.65-ps input pulses by selecting suitable system parameters such as initial intensity and waveguide length which will significantly influence the optical properties of the output pulse, including its time domain waveform, frequency spectrum, and phase chirp. The time duration of the corresponding autocorrelation trace can also reach as little as ~1.0-ps at the end of the device.
    The European Physical Journal D 12/2011; 65(3). DOI:10.1140/epjd/e2011-20376-8 · 1.40 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We theoretically prove a multifunctional photonic differentiation (DIFF) scheme based on phase demodulation using two cascaded linear filters. The photonic DIFF has a diversity of output forms, such as 1st order intensity DIFF, 1st order field DIFF and its inversion, 2nd order field DIFF, dependent on the relative shift between the optical carrier and the filter's resonant notches. As a proof, we also experimentally demonstrate the DIFF diversity using a phase modulator and two delay interferometers (DIs). The calculated average deviation is less than 7% for all DIFF waveforms. Our schemes show the advantages of flexible DIFF functions and forms, which may have different optical applications. For example, high order field differentiators can be used to generate complex temporal waveforms. And intensity differentiators are useful for ultra-wideband pulse generation.
    Chinese Physics B 08/2013; 23(3). DOI:10.1088/1674-1056/23/3/033201 · 1.39 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: An all-optical second-order temporal differentiator using a mechanically-induced long-period fiber grating (MI-LPFG) with a single π-shift was demonstrated. The MI-LPFG was created by pressing a fiber between two periodically grooved plates with a π-shift located at the 3/4 length from the input end of LPFG. The coupling coefficient (κ) can be adjusted by changing the pressure applied on the fiber. The experimental results show that the transfer function of the proposed MI-LPFG can be adjusted to have a transfer function as an ideal second-order differentiator. The differential performance of the designed differentiator to a Gaussian pulse is also analyzed.
    09/2012; 5(3). DOI:10.1007/s12200-012-0272-z