Depolarization technique for wavelength conversion using four-wave mixing in a dispersion-flattened photonic crystal fiber

Department of Electronic Engineering, The Chinese University of Hong Kong, Hong Kong, 00, Hong Kong
Optics Express (Impact Factor: 3.49). 08/2005; 13(14):5409-15. DOI: 10.1364/OPEX.13.005409
Source: PubMed


We have developed a depolarization technique to achieve polarization-insensitive wavelength conversion using four-wave mixing in an optical fiber. A maximum conversion efficiency of -11.79 dB was achieved over a 3 dB bandwidth of 26 nm in a 100-m-long dispersion-flattened photonic crystal fiber. The polarization-dependent conversion efficiency was less than 0.38 dB and the measured power penalty for a 10 Gbit/s NRZ signal was 1.9 dB. The relation between the conversion efficiency and the degree of polarization of the pump was also formulated.

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    • "Another method to overcome the polarization dependence is polarization diversity, in which the pump is split into two orthogonal states that independently interact with the data [16]–[20]. A related approach is to depolarize the pump pulse train, which requires a fiber delay that is longer than the coherence length of the pump laser [21]. "
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